This article compares characteristics of families, mothers, and children on the basis of whether their household is multigenerational, using data from Welfare, Children, and Families: A Three-City Study, which samples low-income culturally diverse families. Few differences were found between multigenerational and nonmultigenerational households, although mothers in multigenerational households reported more internalizing behaviors and fewer positive behaviors in their children. However, interactions between household type, mothers' age, and race/ethnicity reveal that all multigenerational households are not alike. Multigenerational households with younger mothers tend to use less effective parenting and have children who are experiencing more problem behaviors. Race/ethnicity further moderates these associations in models predicting mothers' mental health and children's academic achievement. Possible reasons for these differences by mothers' age and race/ethnicity are discussed. (Contains 6 tables, 7 figures, and 3 notes.)