This study examined the intergenerational transmission of psychopathology symptoms with 7–12 year-old children (N = 97; 44 boys, 53 girls, M age = 9.14, SD = 1.38) and their mothers (M age = 38.46, SD = 6.86). Child emotion regulation mediated the links between maternal psychopathology and child internalizing and externalizing symptoms. In turn, the indirect effect was dependent on the level of maternal support in response to youth’s expressions of negative emotions when considering particular constellations of maternal reactions and type of psychopathology symptoms. The findings indicate that the relations between maternal and child psychopathology symptoms and child emotion regulation are complex and vary by context. Regardless of the complexity, however, for both internalizing and externalizing symptoms in youth, the results suggest that building adaptive emotion regulation skills is an important target for prevention among children who are at risk for problems due to exposure to maternal psychopathology.