Demographic changes in who becomes a parent, how many children parents have, and the marital statuses of parents and children affect the extent to which parents and adult children provide for each other later in life. We describe these demographic changes and their implications for the help parents and children give each other throughout their adult years. The changing demography of US families has increased both generations' need for family assistance among those already disadvantaged and has exacerbated differences between the socioeconomically advantaged and disadvantaged in the availability of kin support. Variations in the marital histories of parents and children also contribute to a divergence between mother-child and father-child relationships in later life. The churning of couple relationships in both generations blurs the boundaries between who is in the family and who is not, threatening the effectiveness of the family safety net among those who may need it the most.
Keywords: exchange; family support; inequality; intergenerational relationships; kin networks; life course.