Melly, who was bisexual, moved from strictly homosexual relationships in his teens and twenties to largely heterosexual relationships from his thirties onwards. He married twice and had a child from each marriage, though his first child Pandora was not known to be his until she was much older. He married his second wife, Diana Moynihan (née Dawson), in 1963 and they lived on Gloucester Crescent in Camden Town. She brought with her two children (Candy and Patrick) from two previous marriages. Patrick died from a heroin overdose in his twenties. Their own son, Tom, was born two days after the wedding. Diana published an autobiography in 2005 of their life and (open) marriage together. The two participated in a televised celebrity couples quiz in the 1970s. Asked separately what made them decide to marry, Diana announced "I was pregnant!" and George, in his turn, merely said, "The less said about that, the better."