The effects of environmental conditions on child mortality were modified by age and early-life conditions. The plotted data shows interactions between variables which improved the fit of models of child mortality. (A) In older children, early-life E was not associated with mortality, while in younger children, higher early-life E (fourth quartile) was associated with higher mortality; (B) where current temperatures were warmer, mortality was independent of early-life temperature (ELT), but where current temperatures were cold, cooler early-life temperatures (first quartile) were associated with higher mortality; (C) mortality in older children was relatively unaffected by early-life temperature, but younger children showed higher mortality if they were born in cold years; (D) mortality in older children was slightly higher if current temperatures were lower, but in younger children, the effect of cooler temperatures on mortality was much stronger. Points show mean mortality, bars represent ± 1 SE.