Family Complexity, Siblings, and Children’s Aggressive Behavior at School Entry

Paula Fomby, University of Michigan
Joshua Goode, University of Colorado at Denver
Stefanie F. Mollborn, University of Colorado at Boulder

As family structure in the United States has become increasingly dynamic and complex, children have become more likely to reside with step- or half-siblings through a variety of pathways. These pathways include living with one’s biological parents and half-siblings who were born in one parent’s prior union; with an unpartnered parent and at least one half-sibling from that parent’s earlier or later union; or with a stepparent and step- or half-siblings in a parent’s new union. When these family structures are accounted for, about one in five children in the United States lives with a step- or half-sibling at age 5. We assess the independent and joint influence of residing with a single parent or stepparent and with step or half-siblings on children’s aggressive behavior at school entry. We draw on a resource-based perspective to explain why the presence of step- or half-siblings might be associated with children’s aggressive behavior.