Investigation of the Effect of Interactive Sibling Education Program on Sibling Relations of Typical Developing Children and Children with Autism

Participants

Autism Spectrum Disorder (ASD) is defined in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) as a neurodevelopmental disorder marked by persistent deficits in social communication and interaction, along with restricted, repetitive patterns of behavior and interests (APA, 2013). These core features are often accompanied by significant intellectual and/or language impairments. Children with ASD typically encounter challenges in social participation, forming peer relationships, and engaging in play activities. Although ASD was considered relatively rare four to five decades ago, its reported prevalence has increased substantially in recent years. Measuring ASD prevalence globally remains a significant challenge due to variations in diagnostic criteria, awareness, and reporting practices (Elsabbagh et al., 2012). For example, the Autism and Developmental Disabilities Monitoring (ADDM) Network has reported biennial estimates of ASD prevalence in 8-year-old children since 2000. Their findings indicate an increase from 1 in 150 children in 2000 (CDC, 2007) to 1 in 36 in 2020 (Maenner et al., 2020).

The family unit is a dynamic system shaped by the behaviors, roles, and interactions of its members. Each member makes a distinctive contribution to the family structure. When a child with a disability is introduced into the family system, it may lead to structural and emotional disruptions that affect the well-being of all members (Gallagher et al., 2006; Harris & Glasberg, 2003; Strohm, 2005; Tsao et al., 2011). The introduction of a child with autism spectrum disorder (ASD) into the family system can disrupt the delicate balance between change and stability, potentially leading to tension and increased psychological burden within the household (Kazak & Marvin, 1984; Luterman, 1987). Families with children diagnosed with ASD often face additional challenges, such as increased stress, altered communication patterns, and evolving familial roles (Karst & Van Hecke, 2012).

While parents are typically the primary agents of socialization, especially in early development (Bronfenbrenner, 1994), the impact of ASD extends beyond parental roles. Siblings, particularly typically developing (TD) ones, are also significantly affected by the presence of a child with ASD in the family. Each family develops unique patterns of functioning and interaction (Strohm, 2005), and events within the family can affect members in different ways. The presence of a sibling with ASD can evoke a wide range of emotional responses in TD siblings, including love, empathy, confusion, frustration, guilt, and jealousy (Yıldırım Doğru & Durmuşoğlu Saltalı, 2011; Ünlü & Gökler, 2021). Despite their vital roles in the social, emotional, and practical development of their siblings with ASD, TD children often receive limited attention and support (Marks, 1998).

The sibling relationship is often described as a "natural laboratory" where children learn essential social skills such as cooperation, communication, empathy, and conflict resolution (Cicirelli, 1994; Minuchin, 1984). Sibling relationships are among the longest-lasting interpersonal relationships in a person’s life and play a formative role in early social development. These relationships are shaped by interactions that often begin in early childhood through play, imitation, and shared experiences (Ahmetoğlu & Aral, 2008; Kryzak & Jones, 2017). TD siblings often become key sources of emotional and practical support (Tsao et al., 2011). From being playmates to confidants and sometimes even rivals, siblings navigate complex emotional terrains together. In families with a child diagnosed with ASD, these dynamics take on an additional layer of complexity. The developmental differences between siblings can lead to communication barriers, emotional distance, or overcompensation, especially during adolescence (Strohm, 2014; Chu et al., 2023).

Given the importance of sibling relationships, targeted interventions for TD siblings represent a promising area of development. Educating and involving TD siblings in structured, evidence-based programs can improve not only their understanding of ASD but also their emotional resilience and social skills. Previous research has shown that such interventions can enhance the quality of sibling interactions, increase the frequency of prosocial behaviors, and promote the generalization of social skills in children with ASD (Shivers & Plavnick, 2015; Tsao & Odom, 2006; Zucker et al., 2022).

The current study focuses on the Interactive Sibling Education Program (ISEP), a structured, home-based intervention that positions TD siblings as active facilitators in the developmental process. The program aims to improve core target behaviors (seeking help, imitating, and game playing) in children with ASD, while simultaneously enhancing the sibling relationship. By equipping TD siblings with the tools, strategies, and emotional support necessary to interact meaningfully with their siblings, the ISEP addresses an often-overlooked area of autism intervention and family support.

METHOD

Design

In the current study, the effect of the ISEP on the relationships of TD children with their siblings with ASD was examined using a multiple- baseline design across behaviors, which is one of the single subject research methods. The content of the education program was determined using the Delphi technique. The content of the program consisted of the target behaviors of game playing, imitating and seeking help.

The program was implemented in the homes of the participating children for 12 weeks, with two sessions per week and a total of 24 sessions. In addition, it was observed whether the gains in target behaviors continued or not with 3 follow-up level sessions held one month after the program was completed.

The study group of the research consists of 4 autistic children, their siblings and their mothers, determined through criterion sampling. The criteria for children with ASD were that they were between the ages of 6–9, had been diagnosed with ASD, and had no additional diagnosis.

The criteria for TD children were that they were between the ages of 10–12, did not have any diagnosis, had a complete family, had not previously been involved in any educational program related to their siblings, and participated in the research voluntarily. Demographic data of the TD children and their siblings with ASD who participated in the study are shown in Table 1.

Table 1
Demographic characteristics of TD children and their siblings with ASD
TD child (T) and sbling with ASD (A)	Sex (M/F)	Age	Number of siblings	Birth order	School	Diagnosis age
T1	F	10	2	1	Secondary	-
A1	M	9	2	2	Primary	6
T2	M	12	2	1	Secondary	-
A2	M	9	2	2	Primary	5
T3	F	12	2	1	Secondary	-
A3	M	9	2	2	Primary	3
T4	M	12	4	2	Secondary	-
A4	M	7	4	3	Primary	3

[ Table 1]

The study group was formed among the families of students who met the criteria and volunteered to participate in the research, attending a special education practice school in Kırıkkale province. T4, one of the TD children, left the study voluntarily after the 13th session, stating that he did not want to participate in the study. The research ended with 3 autistic children, their siblings and their parents.

Procedure

ISEP is a home-based early intervention program designed to enhance the quality of sibling relationships between TD children and their siblings with ASD. The program includes structured teaching plans that target three core behaviors: seeking help, imitating, and game playing.

ISEP was developed based on the Taba-Tyler curriculum development model, a rational and systematic approach that integrates elements from both Hilda Taba’s inductive model and Ralph Tyler’s objectives-based framework. This hybrid model has been widely utilized in educational program design due to its structured and goal-oriented nature (Ornstein & Hunkins, 2017; Print, 1993). Tyler (1949) emphasized defining clear educational objectives and aligning them with instructional methods and evaluation, while Taba (1962) advocated for a grassroots, teacher-driven approach that begins with identifying student needs. Combining these perspectives allows for both top-down strategic planning and bottom-up responsiveness to learner characteristics.

In this study, the Taba-Tyler model was particularly suitable due to its emphasis on needs assessment and behavioral objectives, which align with the individualized requirements of TD children who have siblings with ASD. The model’s initial phase, identifying learner needs, was operationalized through a Delphi Technique, a structured method for achieving expert consensus. This process was carried out in three iterative rounds with 19 experts in fields including child development, special education, and curriculum design. The Delphi results led to the identification of three core behavioral targets for the program: seeking help, imitating, and game playing, which are widely recognized as foundational skills in sibling-mediated interventions for children with ASD (Shivers & Plavnick, 2015; Tsao et al., 2011).

By grounding the ISEP in the Taba-Tyler framework, the program gains both a strong theoretical foundation and the flexibility to meet individual needs. This approach ensures that the instructional content is not only aligned with key developmental objectives, but also tailored to the practical realities of sibling relationships in families with a child diagnosed with autism.

Following this, the ISEP was drafted by the researchers and reviewed by 11 field experts. Expert feedback was used to revise and finalize the program's content and structure. The finalized ISEP consisted of at least three baseline sessions and 21 intervention sessions.

To evaluate the effectiveness of the ISEP, multiple types of data were collected: (a) effectiveness data through baseline, intervention, and follow-up sessions as well as the Schaeffer Sibling Behavior Rating Scale (SSBRS; Schaeffer & Edgerton, 1979) administered pre- and post-intervention; (b) reliability data, which included interobserver agreement and treatment fidelity; and (c) social validity data obtained via semi-structured interviews with mothers (Wolf, 1978).

Prior to implementation, informed consent was obtained from families, and ethical clearance was granted by a special education practice school.

A preliminary home-based meeting was conducted with each family, involving the parents and the TD child, to inform them about the research process. Demographic information was gathered using a General Information Form. Pre-test data were obtained by administering the SSBRS to TD children.

All sessions took place in the families' homes in a pre-designated room, ensuring consistency in environmental settings across sessions. To minimize distraction, electronic devices were turned off during sessions, and only the researcher, the TD child, and the sibling with ASD were present.

Baseline sessions aimed to observe spontaneous interactions between the TD child and their sibling with ASD in terms of game playing, imitation, and seeking help. No instructional intervention was provided by the researcher during these sessions. Each baseline session lasted approximately 15–20 minutes and was video-recorded for coding purposes.

Once stable baseline data were obtained, intervention sessions commenced. Before each intervention session, the TD child received a 15–20-minute individualized training session from the researcher. Following this, the sibling with ASD was brought into the room for the dyadic intervention session, which also lasted 15–20 minutes. These sessions were similarly recorded and no researcher intervention occurred during sibling interactions. To ensure consistency across participants, the researcher provided the same materials, toys, and teaching aids in each session (Ledford & Gast, 2018).

To assess the maintenance of learned behaviors, follow-up sessions were conducted at 37, 44, and 51 days post-intervention. These sessions followed the same procedures as baseline sessions, with data collected to evaluate the long-term effects of the ISEP.

A known challenge of multiple baseline designs is the covariance effect, where instruction on one target behavior may inadvertently influence other non-targeted behaviors (Tekin-İftar, 2018; Cooper et al., 2020). To control for this, the sequence of targeted behaviors were varied among participants.

Data Analysis

ISEP was designed to target three core social behaviors (imitating, seeking help, and game playing) that facilitate meaningful interactions between TD children and their siblings with ASD. Each target behavior was operationally defined to ensure consistency in data collection and analysis:

Imitating was defined as the TD child's ability to perform predetermined imitation activities alongside their sibling with ASD.

Seeking help referred to the TD child’s facilitative behaviors that prompted their sibling with ASD to request assistance.

Game playing was characterized by the TD child’s engagement in structured or unstructured play activities with their sibling with ASD, with or without the use of play materials, in accordance with a predefined purpose.

To assess these behaviors, scoring forms were developed for each target behaviors. These forms included detailed, observable indicators for each behavior, thereby standardizing assessment procedures across observers and ensuring the reliability of data collection. For example, the Scoring Form of Game Playing (Table 2) consisted of 12 behavior-specific items, such as initiating play, offering choices, sustaining joint attention, encouraging turn-taking, and resolving conflicts during play. Each observed behavior was scored dichotomously as present or absent during the session, allowing for the calculation of behavior accuracy.

Table 2
Scoring Criteria for Game Playing Behavior
Item no	Behavioral Indicators of Game Playing
1	Initiates play by inviting the sibling (e.g., “Come on, let’s…”).
2	Provides clear and concise instructions.
3	Offers the sibling a choice of activity or materials.
4	Allows exploration of toys/objects before the game begins.
5	Redirects attention if the sibling becomes distracted.
6	Executes the activity as intended (e.g., rolls ball, bathes doll).
7	Encourages turn-taking.
8	Reinforces sibling’s positive responses (e.g., “Well done!”).
9	Participates in the play while assigning roles to the sibling.
10	Uses descriptive and explanatory language.
11	Addresses challenges with a positive approach.
12	Closes the activity with an expression of gratitude.

[Table 2]

All sessions were video-recorded and later analyzed using the relevant data registration forms for each target behavior (imitating, seeking help, and game playing). The percentage of correct behavior was calculated for each session using the formula:

Percentage of correct behavior = (Number of correct behaviors/Total number of behaviors) x 100

The research employed a single-subject research design, and data were analyzed primarily through graphical analysis, which is standard in such designs (Scruggs et al., 2006; Tekin-İftar, 2018). Specifically, time-series graphs were constructed for each participant. The session numbers were plotted on the horizontal axis, while the percentages of correct behaviors exhibited by TD children were represented on the vertical axis. This visual representation facilitated the examination of changes in target behavior across baseline, intervention, and follow-up phases, allowing for the evaluation of both immediate and sustained program effects.

Reliability

To ensure the credibility and consistency of the findings, two forms of reliability data were collected in the study: interobserver reliability and procedural fidelity. For this purpose, 30% of the session recordings were randomly selected and independently evaluated by two observers. Observer 1 was a doctoral-level academic specializing in child development, while Observer 2 was a special education teacher with six years of field experience. Both observers were trained on the data registration forms and evaluation criteria prior to data analysis to maintain uniformity in coding.

Social Validity

To assess the social validity of the ISEP, qualitative data were collected through semi-structured interviews with the mothers of participating children. A six-item open-ended interview form was developed to explore parents’ perceptions of the program's effectiveness, relevance, and impact on sibling relationships.

The interviews were conducted face-to-face with the mother in the participants’ homes, following the completion of the intervention phase. Each interview lasted approximately 20 to 25 minutes and was video recorded with the informed consent of the parents.

RESULTS

Findings about the Effectiveness Data of the ISEP

In order to determine the effectiveness of the ISEP the targeted behaviors were analyzed and graphically represented. In each graph, the horizontal axis indicates the session number while the vertical axis shows the percentage of correct behavior that TD children showed in those sessions for that target behavior. Graphs were drawn according to the order of implementation of the target behaviors, and the phases of baseline level, intervention level and follow-up level were separated from each other by the phase change line.

For participant T1, the program was implemented sequentially in the order of game playing, seeking help, and imitating (Fig. 1).

Fig. 1

Percentage of Correct Target Behaviors Across Sessions for T1

[Figure 1]

Game Playing Behavior

During the baseline phase (3 sessions), the mean percentage of correctly exhibited behaviors was 30.36%. In the intervention phase, this percentage increased substantially to 74.96%. In the follow-up phase, consisting of 3 sessions conducted after the program was completed, the mean percentage remained high at 76.57%, indicating sustained performance.

Seeking Help Behavior

A total of 10 sessions were conducted during the baseline phase, with an average correct behavior rate of 30.12%. During the intervention phase, the average correct behavior rate rose to 69.59%. In the follow-up phase, the average was 71.49%, suggesting maintenance of the target behavior post-intervention.

Imitating Behavior

During the baseline phase (16 sessions), the mean percentage of correct behavior was 30.86%. In the intervention phase (8 sessions), the average increased to 77.33%. The follow-up session showed a mean of 73.81%, indicating that gains were largely maintained.

These results demonstrate a marked improvement in all three target behaviors during the intervention phase and sustained performance during follow-up, suggesting that the ISEP had a positive and lasting effect on the sibling interactions of TD children with their siblings with ASD.

For participant T2, the ISEP was implemented sequentially in the order of seeking help, imitating, and game playing (Fig. 2).

Fig. 2

Percentage of Correct Target Behaviors Across Sessions for T2

[Figure 2]

Seeking Help Behavior

During the baseline phase (4 sessions), the mean percentage of correct behavior was 13.81%. This value increased significantly to 78.41% during the intervention phase, which included 20 sessions. In the follow-up phase, the percentage of correctly exhibited behavior further improved, reaching 87.98%, indicating a strong maintenance of gains.

Imitating Behavior

The baseline phase consisted of 11 sessions, during which the average correct behavior rate was 30.82%. During the intervention phase (13 sessions), this rate increased markedly to 89.36%. The follow-up phase showed continued stability, with an average of 89.63% correct behavior.

Game Playing Behavior

In the baseline phase (19 sessions), the average correct behavior was 34.24%. During the intervention phase (5 sessions), this rate increased sharply to 92.82%. In the follow-up phase, the behavior was maintained at a high level, with a mean of 90.85%.

These findings suggest that participant T2 demonstrated substantial improvements in all targeted behaviors, with high levels of behavioral maintenance observed in the follow-up sessions.

For participant T3, the program was implemented in the order of imitating, game playing, and seeking help (Fig. 3).

Fig. 3

Percentage of Correct Target Behaviors Across Sessions for T3

[Figure 3]

Imitating Behavior

The baseline phase consisted of 3 sessions, during which the mean percentage of correct behavior was 32.22%. This value rose to 78.77% during the intervention phase (21 sessions). In the follow-up phase, the behavior continued to improve, with a mean of 84.94%.

Game Playing Behavior

During the baseline phase (10 sessions), the average correct behavior was 33.40%. This percentage increased to 80.27% during the intervention phase, which included 14 sessions. The follow-up phase showed stable maintenance of this behavior, with an average of 80.65%.

Seeking Help Behavior

The baseline phase included 17 sessions, with an average correct behavior of 33.43%. During the intervention phase (7 sessions), the average increased to 83.23%. In the follow-up phase, a further increase was observed, with a mean of 87.76%.

Overall, the data from participant T3 indicate notable improvements across all targeted behaviors, with consistent maintenance or enhancement of these behaviors observed during the follow-up period.

Findings of the Schaeffer Sibling Behavior Rating Scale (SSBRS)

In order to evaluate the quality of sibling relationships between TD children and their siblings with ASD, the Schaeffer Sibling Behavior Rating Scale (SSBRS) was administered prior to and following the implementation of the ISEP. Within the scale, the subscales of kindness, involvement, and empathy reflect positive and desirable behaviors, and thus, increases in these scores indicate improvement. In contrast, avoidance and physical aggression are regarded as undesirable behaviors, with lower scores on these subscales reflecting positive developmental change.

[Figure 4]

Fig. 4

Pre- and Post-Intervention Subscale Scores on the SSBRS for T1

For participant T1, post-intervention scores demonstrated a notable improvement across positive subscales (Fig. 4). The kindness score increased from 30 to 36, representing a 20.00% rise. The involvement subscale showed a marked increase from 21 to 32 (52.38%), and the empathy score improved from 20 to 23 (15.00%). Conversely, scores on undesirable behavior dimensions declined: avoidance decreased from 18 to 8 (55.56%), and physical aggression dropped from 10 to 3 (70.00%).

[Figure 5]

Fig. 5

Pre- and Post-Intervention Subscale Scores on the SSBRS for T2

For participant T2, as illustrated in Fig. 5, the kindness score rose from 33 to 40 (21.21%), while the involvement score showed a substantial increase from 20 to 35 (75.00%). The empathy score also increased from 21 to 25 (19.05%). However, the avoidance score remained unchanged at 6, and the physical aggression score showed a modest decline from 5 to 4 (20.00%).

[Figure 6]

Fig. 6

Pre- and Post-Intervention Subscale Scores on the SSBRS for T3

For participant T3, as illustrated in Fig. 6, the kindness score increased from 33 to 36, indicating a 9.09% improvement. The involvement score rose from 23 to 28 (21.74%), and the empathy score increased from 22 to 24 (9.09%). In terms of undesirable behaviors, the avoidance score slightly decreased from 8 to 7 (12.50%), while the physical aggression score declined from 5 to 4 (20.00%).

Overall, the results of the SSBRS indicate that the ISEP had a positive impact on enhancing prosocial sibling behaviors while reducing or maintaining low levels of undesirable behaviors across all three participants.

Social Validity Findings

The qualitative data obtained from semi-structured interviews were analyzed using descriptive analysis and evaluated under four main themes. Since only mothers participated in the interviews, they were coded as M1, M2, and M3. TD children were coded as T1, T2, and T3, and their siblings with ASD were coded as A1, A2, and A3.

Situation Before the Program

Participants were asked to describe the interaction skills between the TD child and their sibling with ASD before the program. The responses revealed that interactions between the siblings were limited and not at the desired level.

M1 stated, "Their time together was very short, and they would fight constantly. They were spending more time on tablets and phones."

M2 explained, "T2 was very insistent with his brother before the program. He didn't understand what his brother wanted or whether he wanted to play games with him. They couldn't do anything together for an extended period."

M3 commented, "The sibling relationship was good, but they lacked the ability to play together. They spent limited time together."

Thoughts about the program

When asked for their opinions regarding the program, all three mothers expressed positive views, emphasizing its effectiveness in improving sibling interactions.

M1 shared, "T2 learned how to build a friendship with his brother. I believe the program is crucial for sibling relationships. I am very pleased with it."

M2 stated, "I think its contribution to sibling relationships is very significant. They will always support each other throughout their lives. This program will benefit them not only now but also in the future."

M3 noted, "A3 used to avoid game-based activities. Through this program, he started engaging in games like logic puzzles. Sometimes, he even holds my and his sister’s hands and invites us to play. This type of communication has positively influenced our thoughts about the program."

Contributions of the Program

Mothers reported that the program had positive effects on the TD children, their siblings with ASD, parental roles, and overall sibling relationships.

Regarding interaction skills, M3 said, "T3 started spending more time with her brother. She discovered different aspects of his personality and offered considerable support throughout this period."

Concerning communication skills, M2 stated, "Before the training, T2 cared about his brother but didn't understand him. Now, he better understands what his brother wants or doesn't want."

Discussing behavioral changes in the child with ASD, M3 observed, "I see that T3 acts more calmly in situations where his brother is impatient. I also noticed that A3's ability to wait has improved. He used to be impatient but has become more compliant."

In terms of play behaviors, M1 noted, "A1 now plays more frequently with his sister. He spends less time on the phone and tablet."

Highlighting the program's impact on parental experiences, M1 added, "T1 and A1 used to fight constantly and always came to me with complaints. This has significantly decreased. They now resolve issues between themselves."

Parental Suggestions Regarding the Program

Participants were asked to provide suggestions for improving the program following its implementation. Their recommendations were as follows:

Regarding content enrichment, M1 suggested, "Reading and writing skills can also be taught through game-based activities."

M2 recommended, "Children with autism could be supported in the area of speech and language development. Training for families on this topic would be beneficial."

M3 proposed, "I think the most challenging aspect for families is teaching personal care skills. For example, toilet training could be included. This type of training could be provided to parents."

Reliability

Interobserver reliability data were obtained by two independent observers who evaluated one session from the baseline, seven from the intervention, and one from the follow-up phases for each participant (T1, T2, T3). Interobserver agreement during the baseline phase was 100% for all participants. During the intervention phase, reliability ranged between 94.21% and 97.91%, while in the follow-up phase, it ranged between 94.44% and 100%.

Procedural fidelity, assessed for randomly selected sessions, was 100% for Observer-1 and 97.17% (range = 87.5–100%) for Observer-2.

DISCUSSION

This study aimed to examine the effect of the ISEP on the relationship between TD children and their siblings with ASD. In this section, the findings regarding TD children's game-playing, imitation, and help-seeking behaviors with their siblings with ASD are interpreted and discussed in light of the relevant literature.

A review of the literature reveals that sibling-mediated interventions have been utilized across a variety of developmental domains, yielding positive outcomes. These include behavioral modification (Colletti & Harris, 1977), academic learning (Schreibman et al., 1983), self-care (Lobato & Tlaker, 1985), daily living skills (Swenson-Pierce et al., 1987), joint attention (Ferraioli & Harris, 2011; Jones & Schwartz, 2004), social interaction (Clark et al., 1989; Gürel Selimoğlu & Özdemir, 2018; James & Egel, 1986; Özen, 2015; Tsao & Odom, 2006), and language development (Spector & Charlop, 2018).

Regarding game-playing behavior, the percentage of correct responses during the intervention phase for T1, T2, and T3 were 74.96%, 92.82%, and 80.27%, respectively. These findings suggest that the program was effective in improving game-playing abilities among participants. Prior to the program, T1's mother noted that the siblings spent minimal time together and preferred screen-based activities. Post-intervention, both T1 and her mother reported increased engagement in shared play activities and reduced screen time. These results align with findings from Tsao and Odom (2006), which indicate that TD children often experience challenges in initiating and maintaining play with their siblings with ASD. In the case of T2, although he enjoyed playing games, his sibling did not respond positively.

The structured support provided by the program, such as initiating games, including the sibling, and following rules, likely contributed to the observed improvements. This is consistent with the findings of Oppenheim-Leaf et al. (2012), where TD children trained in facilitating game interactions saw improvements in shared play. Game-playing is a meaningful context for learning, allowing children to make choices, engage in social interactions, and acquire new skills (Cardinal, 2021; Johnson et al., 2005). It also serves as an effective medium for enhancing sibling interactions.

For seeking help behavior, the percentages of correct behavior in the intervention phase of T1, T2 and T3 were found to be 69.59%, 78.41% and 83.23%, respectively. Children with ASD often have difficulty performing communicative behaviors such as asking for help, refusing and asking questions to meet their needs (Reichle & McComas, 2004). They need support because they can not acquire communication behaviors naturally (Betz et al., 2010). The fact that TD children provide significant support to their siblings in teaching behaviors and skills may be the reason why the implemented program has a positive effect on the siblings. According to the results of the research, the reasons for the increase in asking for help behavior of TD children can be said to be that the program content is prepared in accordance with the target behavior, the teaching strategies are chosen correctly and feedback is given regularly.

With regard to imitating behavior, correct response percentages during the intervention phase were 77.33% for T1, 89.36% for T2, and 78.77% for T3. Imitation is important for all children, whether they have a disability or not. Children with ASD often experience delays in acquiring imitation skills and imitating the actions of others (Bravo & Schwartz, 2022). There are many studies confirming that there is a delay in the acquisition of imitation skills in children with ASD (Charman et al., 1997; Pittet et al., 2022; Stone et al., 1997). Therefore, the interaction bond established between the modeling individual and the child is very important in learning imitation skills (Yamamoto et al., 2019). Teachers, parents, siblings and other family members can provide the guidance and support needed in interaction-based practices (Burkhardt, 2008). In this context, in order to provide interaction support between siblings, a significant increase was observed after teaching imitation skills to their siblings with ASD through TD children.

The sibling relationship is a unique characterized by both love and warmth, but also conflict and competition. However, it is also one of the most neglected relationships in psychological research and practice (Milevsky, 2011). Although sibling relationships extend into adulthood, their foundations are often laid in early childhood. The quality of relationships in the sibling subsystem contributes positively to children's psychological adjustment (Ross & Cuskelly, 2006). While siblings learn to reinforce positive and negative behaviors through imitation, they learn social communication and interaction skills used in different social environments through modeling methods (Farber, 2010). Social interaction is a concept closely related to individuals' communication skills (Baker, 2003). The social interaction that individuals establish with their siblings is important in that it gives them the opportunity to experience many emotions and express their feelings to other people. Also, it contributes significantly to the inclusion of skills such as self-control, sharing, listening, problem solving and playing games into life (Gibbs, 1993).

The Schaeffer Sibling Behavior Rating Scale (SSBRS) was administered before and after the program to assess the impact of ISEP on sibling relationships. The results indicated increased scores in kindness, involvement, and empathy for all participants, suggesting improved interaction quality. Decreases in avoidance and physical aggression scores further support the program's effectiveness.

When the subscale scores of T1 were examined, it was seen that the scores of the kindness, involvement and empathy increased at the end of the program. This is one of the findings showing that T1's behavior towards her sibling has changed positively. The fact that the avoidance and physical aggression scores decreased may indicate that the program had a positive effect on sibling relations. In particular, aggression is one of the most common behavioral problems that occurs in children with ASD during their interactions with their siblings (Ross & Cuskelly, 2006). In the Semi-Structured Interview Form, T1's mother stated that A1 was normally an aggressive child, and for this reason, there were also physical reactions between the siblings. T1's acquisition of information on how to manage A1's negative behaviors during the training may have caused the physical aggression scores to decrease.

The fact that T2's kindness, involvement and empathy scores increased is a finding that shows that the program has improved T2's interaction with his sibling. There was no change in the avoidance dimension scores. His mother stated that T2 made an effort to play games with his sibling and that he did not move away from his sibling even if his sibling showed negative behavior towards him. This is a finding that shows that T2 exhibited positive behaviors in terms of avoidance dimension both before and after the program was implemented.

While T3's kindness, involvement and empathy scores increased after the program, her avoidance and physical aggression scores decreased. This is one of the findings showing that T3's behavior towards her sibling has changed positively and that the program has a positive effect on sibling relationships. The reason why T3 increased proportionally less than other TD children may be that O3 is a calm, moderate child who tries to do her own work, and therefore T3 was gentle and moderate towards her sibling before the program too.

Overall, the findings suggest that the ISEP contributed positively to enhancing the quality of interactions between TD children and their siblings with ASD, promoting prosocial behaviors and reducing negative interactions.

Author Contribution

All authors contributed equally to the conception, design, implementation, analysis, and writing of this study.

REFERENCES

Ahmetoğlu, E., & Aral, N. (2008). Schaeffer kardeş davranışı değerlendirme ölçeğinin Türkçe uyarlaması. Kastamonu Eğitim Dergisi, 16(2), 379–388.

APA (2013). Diagnostic and Statistical Manual of Mental Disorders, 5th ed.

Autism and Developmental Disabilities Monitoring Network Surveillance Year (2000). Principal Investigators, & Centers for Disease Control and Prevention (CDC). (2007). Prevalence of autism spectrum disorders—Autism and Developmental Disabilities Monitoring Network, six sites, United States, 2000. MMWR Surveillance Summaries, 56(1), 1–11. https://www.cdc.gov/mmwr/preview/mmwrhtml/ss5601a1.htm

Baker, J. (2003). Social skills training for children and adolescents with Asperger syndrome and social-communication problems. Autism Asperger.

Betz, A. M., Higbee, T. S., & Pollard, J. S. (2010). Promoting generalization of mands for information used by young children with autism. Research in Autism Spectrum Disorders, 4, 501–508. https://doi.org/10.1016/j.rasd.2009.11.007

Bravo, A., & Schwartz, I. (2022). Teaching imitation to young children with autism spectrum disorder using discrete trial training and contingent imitation. Journal of Developmental and Physical Disabilities, 34(4), 655–672.

Bronfenbrenner, U. (1994). Ecological models of human development. In T. Husén, & T. N. Postlethwaite (Eds.), International Encyclopedia of Education (2nd ed., Vol. 3, pp. 1643–1647). Pergamon.

Burkhardt, S. (2008). The challenge of social competence for students with autism spectrum disorders (ASD). Emerald Group Publishing Limited.

Cardinal, H. (2021). Teaching play skills to children with autism: A review of the literature. BU Journal of Graduate Studies in Education, 13(1), 57–60.

Charman, T., Swettenham, J., Baron-Cohen, S., Cox, S., Baird, G., & Drew, A. (1997). Infants with autism: An investigation of empathy, pretend play, joint attention, and imitation. Developmental Psychology, 33(5), 781–789.

Chu, S. Y., Kassim, S. N. Z. B., Gan, C. H., Fierro, V., Chan, C. M. H., & Hersh, D. (2023). Sometimes I feel grateful… Experiences of the adolescent siblings of children with autism spectrum disorder in Malaysia. Journal of Autism and Developmental Disorders, 53(2), 795–807.

Cicirelli, V. G. (1994). Sibling relationships across the life span. Springer Publishing Company.

Clark, H. B., Striefel, S., Bedlington, M. M., & Naiman, D. E. (1989). A social skills development model: Coping strategies for children with chronic illness. Children's Health Care, 18(1), 19–29.

Colletti, G., & Harris, S. L. (1977). Behavior modification in the home: Siblings as behavior modifiers, parents as observers. Journal of Abnormal Child Psychology, 5(1), 21–30.

Cooper, J. O., Heron, T. E., & Heward, W. L. (2020). Applied behavior analysis (3rd ed.). Pearson.

Elsabbagh, M., Divan, G., Koh, Y. J., Kim, Y. S., Kauchali, S., Marcín, C., Montiel-Nava, C., Patel, V., Paula, C. S., Wang, C., Yasamy, M. T., & Fombonne, E. (2012). Global prevalence of autism and other pervasive developmental disorders. Autism Research, 5(3), 160–179. https://doi.org/10.1002/aur.239

Farber, S. (2010). The effects on siblings of children with autism (Doctoral dissertation, St. John's University). ProQuest Dissertations Publishing.

Ferraioli, S. J., & Harris, S. L. (2011). Effective educational inclusion of students on the autism spectrum. Journal of Contemporary Psychotherapy, 41(1), 19–28.

Gallagher, P., Powell, T., & Rhodes, C. (2006). Brothers & sisters: A special part of exceptional families. Brooks.

Gibbs, B. (1993). Providing support to sisters and brothers of children with disabilities. In G. Singer, & L. Powers (Eds.), Families, disability, and empowerment: Active coping skills and strategies for family interventions (pp. 343–363). Paul H. Brookes.

Gürel Selimoğlu, Ö., & Özdemir, S. (2018). Etkileşim Temelli Erken Çocuklukta Müdahale Programı’nın (ETEÇOM) Otizm Spektrum Bozukluğu sergileyen çocukların sosyal etkileşim becerileri üzerindeki etkililiği. Erken Çocukluk Çalışmaları Dergisi, 2(3), 514–555.

Harris, S., & Glasberg, B. (2003). Siblings of children with autism. Woodbine House.

James, S. D., & Egel, A. L. (1986). A direct prompting strategy for increasing reciprocal interactions between handicapped and non handicapped siblings. Journal of Applied Behavior Analysis, 19(2), 173–186.

Johnson, J. E., Christie, J. F., & Wardle, F. (2005). Play, development and early education. Pearson/Allyn and Bacon.

Jones, C. D., & Schwartz, I. S. (2004). Siblings, peers, and adults: Differential effects of models for children with autism. Topics in Early Childhood Special Education, 24(4), 187–198.

Karst, J. S., & Van Hecke, A. V. (2012). Parent and family impact of autism spectrum disorders: A review and proposed model for intervention evaluation. Clinical Child and Family Psychology Review, 15(3), 247–277. https://doi.org/10.1007/s10567-012-0119-6

Kazak, A. E., & Marvin, R. S. (1984). Differences, difficulties and adaptation: Stress and social networks in families with a handicapped child. Family Relations, 33, 67–77.

Kryzak, L. A., & Jones, E. A. (2017). Sibling self-management: Programming for generalization to improve interactions between typically developing siblings and children with autism spectrum disorders. Developmental Neurorehabilitation, 20(8), 525–537.

Ledford, J. R., & Gast, D. L. (2018). Single case research methodology: Applications in special education and behavioral sciences (3rd ed.). Routledge.

Lobato, D. J., & Tlaker, A. (1985). Sibling intervention with a retarded child. Education and Treatment of Children, 8, 221–222.

Luterman, D. (1987). Deafness in the family. College-Hill.

Maenner, M. J., Warren, Z., Williams, A. R., et al. (2023). Prevalence and characteristics of autism spectrum disorder among children aged 8 years—Autism and Developmental Disabilities Monitoring Network, 11 sites, United States, 2020. MMWR Surveillance Summaries, 72(SS-2), 1–14. https://doi.org/10.15585/mmwr.ss7202a1

Marks, M. G. (1998). Broadribb’s introductory pediatric nursing (5th ed.). Lippincott-Raven.

Milevsky, A. (2011). Sibling relationships in childhood and adolescence: Predictors and outcomes. Columbia University.

Minuchin, S. (1984). Families and family therapy. Harvard University Press.

Oppenheim-Leaf, M. L., Leaf, J. B., Dozier, C., Sheldon, J. B., & Sherman, J. A. (2012). Teaching typically developing children to promote social play with their siblings with autism. Research in Autism Spectrum Disorders, 6, 777–791.

Ornstein, A. C., & Hunkins, F. P. (2017). Curriculum: Foundations, principles, and issues (7th ed.). Pearson.

Özen, A. (2015). Effectiveness of siblings-delivered iPad game activities in teaching social interaction skills to children with autism spectrum disorders. Kuram ve Uygulamada Eğitim Bilimleri, 15(5), 1287–1303.

Pittet, I., Kojovic, N., Franchini, M., & Schaer, M. (2022). Trajectories of imitation skills in preschoolers with autism spectrum disorders. Journal of Neurodevelopmental Disorders, 14(1), 1–13.

Print, M. (1993). Curriculum development and design (2nd ed.). Allen & Unwin.

Reichle, J., & McComas, J. (2004). Conditional use of a request for assistance. Disability and Rehabilitation, 26(21–22), 1255–1262.

Ross, P., & Cuskelly, M. (2006). Adjustment, sibling problems and coping strategies of brothers and sisters of children with autistic spectrum disorder. Journal of Intellectual and Developmental Disability, 31(2), 77–86.

Schaeffer, E., & Edgerton, M. (1979). Sibling behavior to handicapped child inventory. University of North Carolina.

Schreibman, L., O’Neill, R. E., & Koegel, R. L. (1983). Behavioral training for siblings of autistic children. Journal of Applied Behavior Analysis, 16(2), 129–138.

Spector, V., & Charlop, M. H. (2018). A sibling-mediated intervention for children with autism spectrum disorder: Using the natural language paradigm (NLP). Journal of Autism and Developmental Disorders, 48(5), 1508–1522.

Shivers, C. M., & Plavnick, J. B. (2015). Sibling involvement in interventions for individuals with autism spectrum disorders: A systematic review. Journal of Autism and Developmental Disorders, 45(3), 685–696.

Stone, W. L., Ousley, O. Y., & Littleford, C. D. (1997). Motor imitation in young children with autism: What’s the object? Journal of Abnormal Child Psychology, 25(6), 475–485.

Strohm, K. (2005). Being the other one: Growing up with a brother or sister who has special needs. Shambhala.

Strohm, K. (2014). Siblings: Brothers and sisters of children with special needs. David Fulton.

Swenson-Pierce, A., Kohl, F. L., & Egel, A. L. (1987). Siblings as home trainers: A strategy for teaching domestic skills to children. The Journal of the Association for Persons with Severe Handicaps, 12, 53–60.

Taba, H. (1962). Curriculum development: Theory and practice. Harcourt, Brace & World.

Tekin İftar, E. (2018). Eğitim ve davranış bilimlerinde tek denekli araştırmalar (2. baskı). Anı Yayıncılık.

Tsao, L., Davenport, R., & Schmiege, C. (2011). Supporting siblings of children with autism spectrum disorders. Early Childhood Education Journal, 40(1), 47–54. https://doi.org/10.1007/s10643-011-0488-3

Tsao, L., & Odom, S. L. (2006). Sibling mediated social interaction intervention for young children with autism. Topics in Early Childhood Special Education, 26, 106–123.

Tyler, R. W. (1949). Basic principles of curriculum and instruction. University of Chicago Press.

Ünlü, İ., & Gökler, R. (2021). Otizmli çocuğa sahip ailelerde sosyal destek sisteminin önemi. Tıbbi Sosyal Hizmet Dergisi, 18, 194–215.

Wolf, M. M. (1978). Social validity: The case for subjective measurement or how applied behavior analysis is finding its heart. Journal of Applied Behavior Analysis, 11(2), 203–214.

Yamamoto, E., Matsuda, G., Nagata, K., Dan, N., & Hiraki, K. (2019). Subtle temporal delays of mothers’ responses affect imitation learning in children: Mother–child interaction study. Journal of Experimental Child Psychology, 179, 126–142.

Yıldırım Doğru, S. S., & Durmuşoğlu Saltalı, N. (2011). Erken çocukluk döneminde özel eğitim. In S. S. Yıldırım, & Doğru (Eds.), Erken çocukluk döneminde özel eğitim. Maya Akademi.

Zucker, A., Chang, Y., Maharaj, R., Wang, W., Fiani, T., McHugh, S., Feinup, D. M., & Jones, E. A. (2022). Quality of the sibling relationship when one sibling has autism spectrum disorder: A randomized controlled trial of a sibling support group. Autism, 26(5), 1137–1152.

TABLES

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