We examined differential treatment of siblings (maternal involvement, discipline, children's chores) in 2 contexts: families with and without a disabled child. Further, we assessed the connections between differential treatment and both children's adjustment and sibling relationships. Subjects were 62 children, 8–14 years old, half with younger disabled siblings and half with younger nondisabled siblings. In home interviews children rated their adjustment and sibling relations, and mothers reported on discipline strategies used with each child. In 7 nightly phone interviews, mothers recalled durations of specific activities with each child and each child's chores during that day. Analyses revealed greater levels of differential treatment in families with disabled children but no context differences in the correlations between older and younger siblings' treatment. Dimensions of differential treatment were linked to children's adjustment and sibling relationships, and some of these links differed across context.