Drawing on five waves of longitudinal data from 392 families (52% female; mean age of wave 1 [Mage_W1] = 12.89, standard deviation [SD] = .48; Mage_W5 = 21.95, SD = .77; 199 European American and 193 Mexican American families; 217 intact and 175 stepfather families), this study documented transactional relations of mothers’ and fathers’ depressive symptoms with youth's symptomatology from early adolescence to young adulthood. Trait and time-varying cross-lagged models revealed that both mothers’ and fathers’ between- and within-person differences in depressive symptoms were associated with youth's internalizing and externalizing symptoms. Whereas each parent's depressive symptoms uniquely contributed to youth's internalizing symptoms, however, only mothers’ depressive symptoms influenced youth's externalizing symptoms. Although reciprocal effects of youth's internalizing symptoms on parents’ depressive symptoms were not significant, youth's externalizing symptoms predicted changes in mothers’ depressive symptoms over time. Moderation analyses revealed distinct transactional patterns by family ethnicity and child gender, but not by family structure. This study revealed dynamic transactions among family members’ symptomatology that point to opportune times and targets for intervention efforts aimed at mitigating the negative impact of parents’ depressive symptoms on youth's adjustment.