China's 1979–2015 one-child policy was replaced by a two-child policy in 2016. This unanticipated legislative change allowed researchers to analyze labor market discrimination against expected family duty workers. In a two-wave correspondence research, they sent 8,848 fake resumes to job ads, altering gender and sibling status. The study indicated that expected family duties discriminated against women in the job market, but not males, and rose with reproductive age.