This paper points to a sibsize revolution that occurred among children in
lower status families in the United States in the closing decades of the twentieth
century. It interprets that revolution as a source of social convergence in children’s
family contexts that ran counter to trends towards social divergence caused by
change in family structure and has implications for how we understand the impact
of family change on social inequality. Using micro-data from the Census of
Population and Current Population Survey, the paper presents new estimates of
differentials in sibsize and family structure by race and maternal education in the
United States for the period 1940-2012. The estimates suggest that as the share of
lower status children living in mother-headed families rose in the 1970s and 1980s,
their average sibsize declined. The paper discusses some substantive and
methodological challenges for existing scholarship arising from these cross-cutting
movements and points to questions for future research.