We examined whether positive child-, parent-, and family-level characteristics were associated with harsh parenting in families with 9-month-olds (N = 561). We were particularly interested in examining evocative gene-environment correlation (rGE) by testing the effect of birth parent temperament on adoptive parents’ harsh parenting. Additionally, we examined associations among adoptive parents’ own temperaments, marital relationship quality, and parenting. Adoptive fathers’ harsh parenting was inversely related to marital quality and to birth mother positive temperament, indicating evocative rGE. Adoptive mothers’ and fathers’ negative temperaments were also associated with harsh parenting. Findings suggest the importance of enhancing positive family characteristics in addition to mitigating negative characteristics, as well as engaging multiple levels of the family system to prevent harsh parenting.