This article examines the role of the shared family context in understanding differential parental treatment of children. Child-specific and family-context predictors of differential parental positivity and negativity were examined using multilevel modeling in a population of 8,476 children nested in 3,762 families. Child age was the strongest child-specific predictor of positivity and differential positivity. Lower socioeconomic status (SES), marital dissatisfaction, and larger family size were associated with higher levels of differential positivity. There was evidence of potentiation when risks were combined. Children's temperament was associated with parental negativity and differential negativity. The strength of this association was moderated by SES. Mixed-gender sibships in families with marital dissatisfaction and children in single-parent families received the highest levels of differential negativity. The findings are discussed in the context of shared and nonshared environmental influences on development.