Volume 43 - Article 17 | Pages 461–500 Author has provided data and code for replicating results

The sibsize revolution in an international context: Declining social disparities in the number of siblings in 26 countries

By Patrick Präg, Seongsoo Choi, Christiaan Monden

Print this page  Facebook  Twitter


Date received:16 Oct 2019
Date published:13 Aug 2020
Word count:5948
Keywords:families, sibship size, social change, social disparities
Additional files:readme.43-17 (text file, 2 kB)
 demographic-research.43-17 (zip file, 59 kB)


Background: One’s number of siblings is an important determinant of many life outcomes, such as educational attainment. In the last century the United States has experienced a ‘sibsize revolution’, in which sibship sizes declined, and which led to a convergence in family circumstances for children. Did this happen in other countries as well?

Objective: This study examines the development of sibship size and social disparities in sibship size in low-fertility countries across the 20th century.

Methods: We analyze sibship size data collected from 111 nationally representative surveys conducted in 26 low-fertility countries across the 20th century.

Results: Average sibship sizes have declined in virtually all countries. Average sibship sizes are socially stratified, with smaller sibship sizes among higher-educated parents. This social disparity in sibship size has declined over time, indicating convergence in most countries. This convergence applies to large families, but not to only-child families.

Contribution: Siblings are an understudied phenomenon in family demography, despite their growing importance in a time of increasingly complex family structures. Given the significance of sibship size for children’s educational outcomes and overall life chances, decreasing social disparities in sibship size suggest greater equality in the intergenerational transmission of advantage.

Author's Affiliation

Patrick Präg - University of Oxford, United Kingdom [Email]
Seongsoo Choi - Sungkyunkwan University, Korea, Republic Of [Email]
Christiaan Monden - University of Oxford, United Kingdom [Email]

Other articles by the same author/authors in Demographic Research

» Fewer mothers with more colleges? The impacts of expansion in higher education on first marriage and first childbirth
Volume 39 - Article 20

Most recent similar articles in Demographic Research

» Recent trends in the Chinese family: National estimates from 1990 to 2010
Volume 44 - Article 25    | Keywords: families, social change

» Retraditionalisation? Work patterns of families with children during the pandemic in Italy
Volume 45 - Article 31    | Keywords: families

» An age–period–cohort approach to disentangling generational differences in family values and religious beliefs: Understanding the modern Australian family today
Volume 45 - Article 20    | Keywords: social change

» Women's employment and fertility in a global perspective (1960–2015)
Volume 43 - Article 25    | Keywords: families

» Between rivalry and support: The impact of sibling composition on infant and child mortality in Taiwan, 1906‒1945
Volume 42 - Article 21    | Keywords: sibship size