The former wife and a son of Ronald Castree, who was jailed for life for the murder of Lesley Molseed, have said they hope he "rots" in prison.
Castree started to beat his wife soon after they were married
Nick Castree, 28, said he, his two brothers and his mother Beverley had suffered years of abuse.
He told BBC Radio Five Live: "He's just not my father anymore. I don't recognise him as my dad . . . he is a very sick and evil man."
Beverley Castree, 52, branded her ex-husband a "vile monster".
The 54-year-old was jailed for a minimum of 30 years at Bradford Crown Court on Monday for the murder of 11-year-old Lesley in 1975.
Ms Castree, who gave evidence which helped to convict her former husband, said she felt "utter relief" at the sentence.
"He is in the right place", she said.
Castree's son said he no longer saw him as his father
Nick Castree said he was not surprised when his father was arrested on suspicion of Lesley's murder.
He said: "It was no surprise. He was sick, he was twisted. He always had a very keen interest in young girls when we were growing up."
He described how when he and his brothers were growing up, his father would take the family to a holiday park, where he would spend every day in the swimming pool.
"He'd be in the swimming dome every day and he'd be watching the children - the girls - in their swimming costumes.
"[He would be] manipulating the fathers, talking to the fathers to get to the girls. He'd win the fathers round.
"But some of the fathers realised what he was doing, they would move away and take their kids to safety."
He added: "I've got to live for the rest of my life knowing who my father is. That is a life sentence. I wish I had a different father."
Ms Castree, who married Ronald when she was just 18, said she suffered physical and mental abuse on a daily basis during their 24-year marriage, but she had not been brave enough to leave him.
The abuse began shortly after their marriage in 1973.
She said: "I'm so angry with him, I hate him so much. I hope he rots in there."