The mother of James Bulger was said yesterday to be devastated by the decision of the European court.
Mrs Denise Fergus, who remarried after her divorce from James's father, stayed away from a press conference in Liverpool in order to attend her son's nativity play.
But her solicitor, Mr Sean Sexton, said she had described the decision as the culmination of her worst fears and felt her son had been overlooked by the judges.
She wanted James's killers to serve the full 15 years determined by the former home secretary, Mr Michael Howard.
"I have spoken with Denise and she is devastated," said Mr Sexton. "She feared the worst and always thought there was a danger of this happening and that they were trying for the minimum sentence.
"She fears now there is a risk they will be released when they have served the minimum tariff [eight years]."
Mr Sexton said Mrs Fergus could "just not envisage" that her son's killers could soon be released, perhaps with an injunction preventing them from being identified.
"She fears if they are let out they might do something similar again," he said. "Denise will do anything she legitimately can to stop this happening." Her only option now was to rally public opinion and lobby the Home Secretary.
Mrs Fergus's brother, Mr Ray Matthews, said: "Denise cannot understand why this keeps going on and on and on. We want it to end, we want it to all stop but we have the lawyers doing their utmost to get these killers out. Why do they put us through all this time and time again?"
He said the family felt utterly powerless to influence a decision which had been taken out of the country. "We believe Denise should have been allowed to speak to the court and tell them how she feels and how she felt after James was murdered."
At another Liverpool press conference, James's father, Mr Ralph Bulger, spoke only to say: "I'm pleased with the decision". He was registering approval of the court's ruling that Robert Thompson and Jon Venables could be held criminally responsible and could be punished.
His solicitor, Mr Robin Makin, insisted the ruling did not mean Thompson and Venables would walk free in two years' time.
Former Det Supt Albert Kirby, who led the murder inquiry and has since retired, said the 15-year sentence for the convicted boys was right. "Mr Howard's judgment was based on the facts. He was not swayed by public opinion.
"There is nothing that we could have done differently. And it should be noted that the European court has raised no criticism of myself or my staff. When people say that they didn't have a fair trial, I disagree. Everything was done in a manner which was the best and was considerate. It was impossible to do it any other way."
Mr Kirby added that it was disgraceful that the convicted boys had been awarded costs by the European Court.
Ms Rosie Cooper, mayor of Liverpool in 1993 at the time of James Bulger's killing, said most people in the city would be angered by the court's ruling. "They are saying that the trial was not fair but I think those boys were very old-headed and knew exactly what they did and what was happening at their trial.
"They were not ordinary innocent 10-year-olds and it is sickening to hear that they should have been dealt with in a child-friendly court. Murder is not very child friendly.
"In all this we should not forget about James. He was the victim and there must be justice for him and his family too."