Haines was born on January 2, 1900 (he claimed he was born on January 1) in Staunton, Virginia, the third child of George Adam Haines, a cigar maker, and Laura Virginia Haines (née Matthews). Two older siblings died in infancy. He had four younger siblings: Lillian, born in 1902; Ann, born in 1907; George, Jr., born in 1908; and Henry, born in 1917. He was baptized at the Trinity Episcopal Church in Staunton at the age of eight, where he later sang in the choir. He became fascinated with stage performance and motion pictures at an early age, spending hours watching early silent films in the local theatres.