Guilt theoretically functions to motivate reparative behaviors, which, in turn, theoretically alleviate guilt and prevent depression. Although empirical research supports these theories in adults, studies have not investigated causal relations between guilt and reparative behaviors in children. Thus, this study examined whether guilt motivates children's reparative behaviors, and whether their reparative behaviors successfully alleviate guilty feelings. Six-to 10-year olds (N = 97) were randomly assigned to 1 of 3 conditions. Children in the experimental condition were led to believe they had transgressed to cause a peer's distress. Children self-reported their guilt following the transgression, and then had the opportunity to repair the transgression by giving stickers and writing a note to the victimized peer. Following the repair opportunity, children self-reported their guilt a second time. Children in the experimental condition (i.e., children who felt guilty) engaged in greater reparative behavior than children in a no-guilt condition who were led to believe they had caused a peer's slightly positive emotions. Further, children in the experimental condition reported reduced guilt across the first to second guilt measurement, whereas children in the no-repair condition (who transgressed but did not have a repair opportunity) did not report reduced guilt over time. Results demonstrate that guilt and reparative behaviors function as theorized in middle childhood and may begin to inform reparative interventions aimed at preventing maladaptive guilt and depression.