James Bulger's dad has demanded that Jon Venables remains behind bars as he seeks a release from prison later this month.
Ralph Bulger said Venables still poses a danger to children and must not be given parole.
The dad and his brother Jimmy have written an impact statement urging Liverpool Crown Court to reject the killer's parole application when he appears via video link.
The Sun reports that the 46-year-old has told friends: "Venables is a murdering and violent sexual predator, from a boy to a man, and nothing has changed.
"He deserves to spend the rest of his days behind bars."
Venables and Robert Thompson were 10 years old when they abducted two-year-old James from a Merseyside shopping centre before torturing and killing him in 1993.
The pair were released on licence in 2001, but three years ago Venables was found to have downloaded child pornography and was sent back to prison. He applied for parole in 2011, but was turned down, and is now eligible to apply again.
James's two killers are both living under assumed identities owing to the risk of vigilante attacks. Venables has had to be given a number of new identities after repeatedly blowing his cover, but Thompson has kept out of legal trouble.
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