Maternal infection during pregnancy increases the offspring's risk of developing neurodevelopmental disorders. While IL-6 is involved, the mechanism by which IL-6 and other cytokines affect developing neural circuits is unknown. In this issue of Immunity, Mirabella et al. (2021) show that the pro-inflammatory cytokine IL-6 specifically increases synaptogenesis in immature excitatory neurons through downstream neuronal STAT3-dependent transcriptional regulation of Rgs4.