Despite the frequency of divorce and remarriage across much of sub-Saharan Africa, little is known about what these events mean for the living arrangements of children. We use longitudinal data from rural Malawi to examine the effects of family transitions on the prevalence and incidence of child fostering, or children residing apart from their living parents. We find that between 7 % and 15 % of children aged 3–14 are out-fostered over the two-year intersurvey period. Although divorce appears to be a significant driver of child fostering in the cross-sectional analysis, it is not significantly associated with the incidence of out-fostering. In contrast, maternal remarriage has both a lagged and an immediate effect on the incidence of out-fostering. Furthermore, the likelihood of out-fostering is even higher among children whose mother remarried and had a new child during the intersurvey period. Using longitudinal data collected from living mothers rather than from children’s current foster homes offers new insights into the reasons children are sent to live with others besides their parents.