Diarrhea and respiratory infections account for more than two-fifths of all deaths among children under five. Parental education and economic status are well-known risk factors for child morbidity, but little is known about whether education and economic status operate synergistically or independently to influence children's health. Confirming the presence and direction of such interactions is important to better target education and development policies. Our objective is to test for interactions between parental education and economic status in predicting the risk of diarrhea and respiratory illness among children under five, before and after adjusting for key proximate risk factors. We pool 12 Demographic and Health Surveys (DHS) and nine Living Standards Measurement Surveys (LSMS) from Latin America, creating two large databases. Quintiles of economic status are constructed from principal components asset indices. We use logistic regression to analyze episodes of diarrhea and respiratory illness, and interactions between economic quintile and maternal and paternal education are evaluated via likelihood ratio tests. We find that mother's education and quintile interact synergistically in the DHS data, while results are inconclusive in the LSMS data. The effect of increasing maternal education appears to be more protective for children in wealthy families than for children in poor families. Conversely, improvements in economic status reduce health risks more for children whose mothers are better educated. Father's education is protective and operates independently of economic status. Our findings imply that poverty alleviation efforts occurring in concert with programs to educate women and girls will be more effective for improving children's health than either approach alone.