We examine affective closeness, contact, and helping among adult siblings using data for over 1,500 respondents in 2-child families from the National Survey of Families and Households. Using this subsample allows us to investigate differences by gender of respondent and of individual siblings using a nationally representative sample. We find that siblings are central to the lives of adults; most sibling relationships involve frequent contact and positive feelings. Sister pairs phone and exchange advice more often than do other sibling pairs. Women are more likely than men to report feeling close to or getting along with their sibling. We find no consistent differences in visiting. Giving and receiving help appear to reflect gendered forms of intimacy and of household labor.