Food insecurity is pervasive and highly seasonal in Ethiopia. In this study, we investigate the effect of seasonal food insecurity on child development. Exploiting the Young Lives Ethiopia dataset, we study the gender-specific impact of in utero exposure to seasonal food insecurity on cognitive development and the probability of being on the expected grade for children of age 8 up to 12. We find that at age 8, in utero exposure to food insecurity negatively affects cognitive development, only for boys. At age 12, such exposure significantly reduces cognitive development for all children, but with a significantly higher magnitude for boys. The impact is almost three times bigger compared to the one estimated for girls. Corroborated with other outcomes, we explain such gender imbalances by the accumulative nature of the scarring effect rather than the culling effect or gender differences in parental investment.