A spokesman for the NSPCC said: "Russell’s campaign of abuse will have had devastating consequences on a victim who tragically died before seeing him finally admit his guilt.
"Thanks to the bravery he showed in speaking out about his ordeal, Russell is now facing the consequences of his depraved actions.
"It’s important that child sexual abuse survivors know they will be listened to when they come forward, no matter how long ago the offences took place.
"Support and advice is available via the NSPCC Helpline, on 0808 800 5000. Children and young people can call Childline on 0800 1111 or get help online via www.childline.org.uk."