We examined play interactions between siblings when one child has autism in a Vietnamese American and a European American family. Analysis was based on video recorded free play sessions with each set of siblings at their home. Interviews with the typically developing sibling and parents also provided supplemental data to aid our knowledge about their play behavior. This study describes the role of the typically developing sibling in play and the types of play engaged in by siblings. Findings indicate that the two sets of siblings differed in their play behavior. Specifically, significant differences were noted in the role of the typically developing sibling in play, and the types of play engaged in by the siblings. The perceptions of the typically developing siblings and parents regarding autism also differed across families, significantly affecting their play behavior. Implications for research are described.