© REUTERS/Kacper PempelCandles and placards are pictured during a protest in support of Alfie Evans, in front of the British Embassy building in Warsaw, Poland April 26, 2018.
Alfie had a rare, degenerative disease and had been in a semi-vegetative state for more than a year.
After a series of court cases, doctors at Alder Hey Children's Hospital in Liverpool removed his life support on Monday, against his parents wishes.
He confounded expectations by continuing to breathe unaided for days, but died in the early hours of Saturday, his parents said.
"My gladiator lay down his shield and gained his wings at 02:30 absolutely heartbroken," the boy's father Tom Evans wrote on Facebook.
"Our baby boy grew his wings tonight ... Thank you everyone for all your support," his mother Kate James wrote.
Medical experts in Britain had agreed that more treatment for Alfie would be futile, but his parents wanted to take him to Rome, where the Vatican's Bambino Gesu hospital had offered to care for him.
A British court rejected an appeal by the parents on Wednesday to take their son to Italy.
The case has provoked strong feelings over whether judges, doctors or parents have the right to decide on a child's life. Alfie's parents have been backed by Pope Francis and Poland's President Andrzej Duda.
Comment: A tragic end to this story. While it's unknown whether the offered treatment in Italy would have saved Alfie, the fact that the NHS essentially held the boy prisoner against his parents' wishes is what's truly disturbing about the case. The parents must be the ultimate arbiter of the fate of their children, not the state. This is a very dangerous precedent for the UK.
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