Research by Wendy Manning of Bowling Green State University and others shows that unmarried Mexican-American couples who have children while living together are slightly more likely to break up than are blacks or whites in similar circumstances.

ECONOMIST: Hispanic families

Forty-four percent of white women married within three years of living together the first time, while 31% of black women and U.S.-born Hispanic women did so.

CNN: Report: More women moving in before marriage

The resigned Vanya (David Hyde Pierce) and his bipolar adopted sister, Sonia (Kristine Nielsen), have been rusticated in this backwater, first looking after their dying parents, and now living together, without work or purpose, while a third sibling, Masha (the droll Sigourney Weaver), a famous actress, supports them from afar.

NEWYORKER: Vanya and Sonia and Masha and Spike

The highest number of people living together is in south east England with more than 30% of people cohabiting while only 10% of people live together in Northern Ireland, the lowest number.

BBC: News | UK | Marriage out of fashion