SBC Multigen was established in 2018/2019, as a result of a probability matching between the Stockholm Metropolitan Study (SMS) and Reproduction of Inequality Through Linked Lives (RELINK). The Stockholm Birth Cohort Study (SBC) was first created in 2004/2005 by a probability matching of the Stockholm Metropolitan Study (SMS; 1953–1985) and The Swedish Work and Mortality Database (WMD; 1980–2009). To enable an extended follow-up of the SMS, the WMD was replaced by a new de-identified data material called RELINK53, which is defined as all individuals born in 1953 and living in Sweden in 1960, 1965, and/or 1968, and their family members. This turned the SBC into a multigenerational data material which is now referred to as the Stockholm Birth Cohort Multigenerational Study (SBC Multigen). SBC Multigen's data material contains information from 14,608 cohort members (as well as their parents, siblings, friends, spouses, and children).