The Birth of a Star
Cher was born in California on May 20, 1946, as Cherilyn Sarkisian to Georgia Holt (born Jackie Jean Crouch), a model and actress of Irish-English-German-Cherokee descent, and John Sarkisian, an American-Armenian truck driver. Georgia Holt divorced Sarkisian and married bank manager Gilbert Hartmann LaPierre in 1961. He legally adopted Cher and her half-sister Georganne.
Source: Dear mom, love Cher Documentary
Her biological father was barely home after she was born, and her parents went their separate ways ten months after her birth. Her mother subsequently married actor John Southhall and gave birth to Georganne.