PIP: The authors examine whether mothers vary in the degree to which they perceive their children as burdensome, and whether this variation explains why past research on the effect of children on mother's psychological distress often finds insignificant or inconsistent effects: mothers who feel their children are a burden may have high distress levels compared with mothers who do not feel burdened. The authors find that mothers experience their children as differentially burdensome at different stages in the life cycle. Younger mothers' perceived burden increases with each additional child, but older mothers are less affected by increasing numbers of children. Preschool children increase all mothers' perceived burden because they tend to make mothers feel that they cannot be alone when they want to. Employed mothers feel less burdened by their children than the nonemployed. Social context--the density of people in the home, integration into the neighborhood, and the presence of relatives in the area--had a number of unexpected effects. Crowding in the home increased the perception that children are burdensome by way of subjective crowding--the perception that there is too much activity in the home, the perceived inability to be alone, and dissatisfaction with living space. However, controlling for subjective crowding, the more adults in the home, the less the burden of children, presumably because these adults can help care for the children. Integration into the neighborhood increased the likelihood of sharing child care with friends and neighbors, but this shared child care increased the perception of burden. Having relatives in the area increased the likelihood that these family members would care for children, but this child care had no significant effect on reducing burden. Instead, relatives in the area increased a mother's perception that she could not be alone when she wanted to, which increased burden. Thus, the authors found a number of costs of social integration for mothers.