This paper presents the conditions under which a causal interpretation can be given to the association between childhood parental employment and subsequent education of children. In a model in which parental preferences are separable in own consumption and children’s well-being, estimation is complicated by endowment heterogeneity and by the fact that parents may compensate or reinforce children’s endowments relevant to educational attainment. A sibling difference estimation strategy is generally not sufficient to provide a consistent estimate of the parameter of interest. Identification rests on two stronger assumptions about the timing of parents’ knowledge of their children’s endowments and about the technology used to produce children’s human capital. We find a negative and significant effect on the child’s educational attainment of the extent of mother’s full-time employment when the child was aged 0-5. The effects of mother’s part-time employment and father’s employment are smaller and less well determined but again negative. In the context of our conditional demand function framework, these results suggest that a higher full family income increases the educational attainment of children, and given full family income, a higher mother’s or father’s wage reduces their children’s educational attainment.