Three youths were given life sentences with minimum terms of 19 years today for killing Ben Kinsella, the 16-year-old brother of actress Brooke Kinsella.
Juress Kika, 19, Jade Braithwaite, 18, and Michael Alleyne, 20, from London, were convicted of murder at the Old Bailey, yesterday.
Ben and his friends had been to a bar to celebrate the end of their GCSE exams when a row broke out in Islington, north London, on June 29 last year.
Although the confrontation had nothing to do with him, he was chased along the street with other youngsters - and stabbed to death when he stopped running.
Ben was stabbed 11 times in five seconds by the three youths in revenge for the "disrespect" shown to Braithwaite earlier.
Former EastEnders actress Brooke Kinsella, 25, said after the verdict: "I am overjoyed.
"It's awful, awful, but we got all we needed - it's justice. There is never going to be enough justice but we have got it now."
Yesterday, father George, 49, said: "Our precious and gentle son Ben was brutally murdered on the streets of London.
"How many families like ours will have to stand outside the Old Bailey to get justice? Our son's only crime was to be the last one to run away from those animals. Knife crime is now sadly embedded in the heart of Great Britain, always running the lives of gangs and feral youths.
"Parents live in fear until their children are safely home.
"It could be a wrong word, a wrong look or the wrong postcode. In Ben's case, it was something which was nothing to do with him at all."
Mother Deborah, 46, told the judge: "We had brought Ben up to always walk away from trouble. This sadly cost him his life.
"He walked away to get safely home and they took advantage of that - he was one boy on his own."
She added: "We, as his family, have been left devastated and in total despair. Our whole world has been totally turned upside down.
"Ben went for a good night out and never came home again."
Kika had been on the run from police for 10 days following a robbery in which a man was knifed on June 19.
Three other youths were arrested but despite extensive searches and inquiries, Kika was not found until he was arrested for Ben's murder at a flat in Chadwell Heath, east London, on June 30.
The 21-year-old victim, who appeared to have been involved in a row about drugs, refused to press charges.
Alleyne was being supervised by the local youth offending team as part of an 18-month detention and training order for drug dealing.
He had been released three months earlier after serving half the sentence in a detention centre.
Braithwaite was given a community order for an attempted robbery in 2007.
During the trial, aspiring footballer Braithwaite and Alleyne tried to blame each other, while Kika refused to give evidence.
Nicholas Hilliard QC, prosecuting, told the court: "No one suggests Ben Kinsella was anything other than totally blameless."
The Common Serjeant of London, Judge Brian Barker, told the defendants that they took part in a "brutal, cowardly and totally unjustified attack".
Their action that night "defies belief", he said.
"His family will never get over it but he will never be forgotten," the judge said.
Brooke Kinsella said following the sentencing: "It's good enough but it is little more than Ben lived, so it is not really enough."
There was loud cheering and shouts of "bye bye" from the public gallery, where dozens of Ben's friends and family gathered as the killers were taken down.
Kika and Alleyne both turned and jeered, making gestures towards them.
Members of the defendants' families exchanged angry words with Ben's friends and relatives before they were led out.
The judge said: "Ben Kinsella was 16 when he died. He had in front of him a lifetime of promise and you have taken all that away from him by a brutal, cowardly and totally unjustified attack.
"The background is depressing and all too familiar in these courts. It reflects the futility of carrying and using knives by some young people.
"Your behaviour generates outrage in all right-minded people and your blind and heartless anger defies belief."
He said there was "no suggestion" Ben had been involved in the trouble preceding the stabbing and was instead trying to get away when he found himself encircled and attacked.
"No attempt was made to help him in any way and not a hint of remorse has been shown by any of you."
The judge said there was "no possible excuse" for what happened.
"I can only deduce that in your minds someone had to pay the ultimate price, whoever that might be.
"What you have done has caused untold anguish," he said.
"This was a terrible attack and you knew exactly what you were doing and you must take responsibility for your actions."
The crime was aggravated by the fact that they picked on "an obviously younger and smaller lone victim", the judge added.