Pope breaks taboo by marrying couples who lived 'in sin'

A single mother, people who have been married before and couples who have been living together "in sin" were married by Pope Francis in a taboo-challenging ceremony at the Vatican on Sunday.

In another signal of the openness of his papacy, Francis asked to marry 40 people from different social backgrounds who would be a realistic sample of modern couples.

Popes very rarely perform marriages -- the last one was in 2000.