The interaction between investment in children's education and parental fertility is crucial in recent theories of the transition from Malthusian stagnation to modern economic growth. This paper contributes to the literature on the child quantity-quality trade-off with new county-level evidence for Prussia in 1816, several decades before the demographic transition. We find a significant negative causal effect of education on fertility, which is robust to accounting for spatial autocorrelation. The causal effect of education is identified through exogenous variation in enrollment rates due to differences in landownership inequality. A comparison with estimates for 1849 suggests that the preference for quality relative to quantity might have increased during the first half of the nineteenth century.JEL Classification: N33, I20, J13