Research Brief Replacing Aggressive Behavior Toward Sibling Barry, L. M., & Singer, G. H. S. (2001). A family in crisis: Replacing the aggressive behavior of a child with autism toward an infant sibling. Journal of Positive Behavior Interventions, 3(1), 28-38. Why was it conducted? Early sibling interactions affect future relationships and the overall functioning of families. This study documents the process and outcomes of behavioral support efforts for a child who displayed aggressive behavior toward his infant sibling. It demonstrates an effective approach to support for a family in crisis. Who participated? The child whose behavior was a focus of this investigation was a 10 year-old with autism. He was engaging in aggressive behavior toward his infant sibling that included smothering, shaking, and choking the baby; overturning the stroller; and encouraging the baby into dangerous situations. In addition to the focus child, participants included the parents, infant, and two other siblings. How was it implemented? The support process was conducted over a 26-month period. The interventionists conducted a functional assessment (i.e., involving observations and interviews) in order to identify circumstances affecting the child’s behavior. They found that the child with autism’s aggressive behavior occurred when in proximity to the infant and resulted in negative verbal – and sometimes physical - attention from parents and siblings. The intervention involved 1) teaching the child replacement behaviors, 2) using self-monitoring and self-recruited praise, 3) coaching the parents and siblings to respond more appropriately to the behavior, and 4) teaching the child to attend to the affect of the infant sibling in response to replacement behaviors. The specific skills were identified by observing the other siblings interact with the infant. The skill training was conducted by a clinician (rather than the family as typically recommended) due to the emotionally-charged nature of the situation. The intervention package was introduced across target behaviors using a non-concurrent multiple baseline design. What were the results? The process resulted in decreases in the child’s aggressive behavior, increases in his use of replacement skills, and improvements in sibling interactions. Over time, the duration of appropriate sibling interaction also increased. Because of the intervention, the child with autism was maintained at home, and the family was no longer in crisis What are the implications? This study provides evidence that clinician-led intervention – while not typically recommended – can be successful. Some unique features of this investigation included identifying replacement behaviors by observing sibling interactions and embedding the intervention in daily routines. Both of these features enhanced the contextual fit of the interventions for the family. In addition, the study illustrates the importance of using a developmental perspective when designing interventions (e.g., strategies were designed to match the age and capacities of the children and changed over time)