Objective: This study focused on whether a brief family-based intervention for toddlers, the Family Check-Up (FCU), designed to address parent management skills and prevent early conduct problems, would have collateral effects on maternal depressive symptoms and subsequent child emotional problems. Method: Parents with toddlers were recruited from the Women, Infants, and Children Nutritional Supplement Program based on the presence of socioeconomic, family, and child risk (N = 731). Families were randomly assigned to the FCU intervention or control group with yearly assessments beginning at child age 2. Maternal depressive symptoms were measured using the Center for Epidemiological Studies Depression Scale at child ages 2 and 3. Child internalizing problems were collected from primary caregivers, alternative caregivers, and teachers using the Child Behavior Checklist at ages 7.5 and 8.5. Results: Structural equation models revealed that mothers in families randomly assigned to the FCU showed lower levels of depressive symptoms at child age 3, which in turn were related to lower levels of child depressed/withdrawal symptoms as reported by primary caregivers, alternative caregivers, and teacher at ages 7.5–8.5. Conclusions: Findings suggest that a brief, preventive intervention improving maternal depressive symptoms can have enduring effects on child emotional problems that are generalizable across contexts. As there is a growing emphasis for the use of evidence-based and cost-efficient interventions that can be delivered in multiple delivery settings serving low-income families and their children, clinicians and researchers welcome evidence that interventions can promote change in multiple problem areas. The FCU appears to hold such promise.