Daughters who are principal caregivers to disabled elderly mothers are compared with their geographically proximate sisters and brothers as to the amount of help each group provides, the effects of care they experience, and the problems and benefits of the siblings' interactions about the caregiving situations. Caregivers reported the most and brothers the least service provision and strain; sisters fell in between, and also equaled caregivers in strain from intersibling problems. Negative intersibling interactions are associated with less emotional closeness in the families and the mothers' greater care needs.