A man whose son was convicted of the torture and murder of Mary Ann Leneghan wants to set up a group to help fathers get more involved with their children.
Adrian Thomas must serve 27 years in prison
Tony Thomas's son Adrian, 20, was one of six men who, raped and tortured the 16-year-old in Reading, Berkshire.
Mr Thomas, of Stockwell, said if he had a better relationship with him he would have "sorted" him out.
He told BBC London he wanted to help fathers build relationships with children they no longer lived with.
Mr Thomas, a father of four, said he was "gutted", "shocked" and "speechless" when he found out about his son's crimes.
He is not with Adrian's mother and has three other children with three different women.
He also admits that he wishes he had played a greater part in Adrian's life.
Mr Thomas said he had tried to get back in touch with him but his son had so far not responded.
He said: "I didn't know until Adrian was found guilty of murder that he was on probation for heroin.
"So all I needed to know was that and I'd have had him sorted.
"When your kids are rebelling against you and they're on the street they're likely to get into things like these.
"There's people out there waiting to manipulate them if you aren't there to offer them guidance."
Mr Thomas is now teaming up with the Families Need Fathers charity to encourage dads to be more involved with their children.
Adrian Thomas, of Battersea, south London , was ordered to serve at least 27 years in prison.