This paper assesses the change over time of within-family inequality in the educational outcomes of Spaniards by measuring the effects of birth order on the number of years of formal education attained in families of different sizes. The analysis is based on data from the 1991 Sociodemographic Survey, adopts the perspective of cohort analysis, and looks at those born in the first six decades of the 20th century. The data reveal that the effects of both the number of siblings and, above all, birth order increased over the cohorts. This means that educational inequalities within Spanish families tended to grow in contrast to inequalities between families in a period of great expansion of the education system. Although the Spanish experience may have differed from that of other developed countries, it fits well within the theoretical framework of conditional dilution of parental resources associated with the number of siblings and birth order.

This paper examines how number of siblings affects employment under the relaxation of the One-Child Policy in China. We explore the One-and-A-Half-Child Policy in 1980s and examine its long-term impact on siblings and employment. With the data from 2010–2018 China Family Panel Studies, we find that individuals tend to have a larger number of siblings and have a higher probability of working in the places where the One-and-A-Half-Child Policy was implemented earlier. Using the degree of the impact of this policy as an instrumental variable for number of siblings, we find that one more sibling would increase the likelihood of working by 9.0 percentage points and increase the likelihood of working in the non-agricultural sector by 5.1 percentage points. Females are more affected by the relaxation than males. We also discuss the major mechanisms through which siblings affect employment. We find that the care-sharing effect of siblings increases labor supply and the social network effect of siblings brings more job opportunities and increases employment. The One-and-A-Half-Child Policy improves the labor market outcomes through both the channel of sharing care and the channel of social network.

Mainstream sociological studies of intergenerational social mobility have emphasised social factors such as education and the material and cultural resources of the family of origin as the main influences on the chances and direction of social mobility. Medical sociology in contrast has been more interested in its physical correlates such as height and health status. Data from the West of Scotland Collaborative study allow an examination of the relationship between social mobility and both social and physical factors. Height, education and material circumstances in the family of origin, indexed as the number of siblings, were each independently associated with the chances of both upward and downward social mobility in this dataset. In each case the net effect of this social mobility was to constrain the social distribution of these variables. Any role which these factors may play in indirect health selection, it is argued, cannot account for social class differences in adult health.