his study tested implications of new genetic discoveries for understanding the association between parental investment and children’s educational attainment. A novel design matched genetic data from 860 British mothers and their children with home-visit measures of parenting: the E-Risk Study. Three findings emerged. First, both mothers’ and children’s education-associated genetics, summarized in a genome-wide polygenic score, predicted parenting — a gene-environment correlation. Second, accounting for genetic influences slightly reduced associations between parenting and children’s attainment — indicating some genetic confounding. Third, mothers’ genetics influenced children’s attainment over and above genetic mother-to-child transmission, via cognitively-stimulating parenting — an environmentally-mediated effect. Findings imply that, when interpreting parents’ effects on children, environmentalists must consider genetic transmission, but geneticists must also consider environmental transmission.