In January, a judge ruled that intensive care treatment could be withdrawn from Isaiah Haastrup, and 11-month-old boy with severe brain-damage, despite his parents' wishes for continued intervention. Alfie passed away at Alder Hey Children's Hospital after he was put on life-support in 2016.
"Our baby boy grew his wings tonight at 2:30 a.m". "My Gladiator laid down his shield and got wings... my heart is absolutely broken", - he wrote.
Earlier in April, Thomas Evans had visited Pope Francis in Rome, pleading with him to "save our son".
Officials in largely Catholic Poland and Italy have criticized Britain's courts and state-run National Health Service.
The case has stirred up the issue of whether judges, doctors or parents have the right to decide on a child's life. Charlie's parents ultimately gave up their fight to take the baby to the US for experimental therapy to prolong his life, saying there wasn't a realistic chance of saving him.
Francis has spoken repeatedly about Alfie.
Alder Hey children's hospital posted a statement on their website saying: "All of us feel deeply for Alfie, Kate, Tom and his whole family and our thoughts are with them".
Five days after a children's hospital yanked his life support without his parent's permission, little Alfie Evans has died.
"The only master of life, from the beginning to its natural end, is God, and our duty is to do everything to protect life", he said.
Alfie garnered worldwide attention during his family's legal battle, even drawing attention from Pope Francis, who tweeted Saturday that he was "deeply moved" by Alfie's death.
Alfie had been in a semi-vegetative state and scans of his brain had shown that nearly all of it had been destroyed.
Under British law, courts are asked to intervene when parents and doctors disagree on the right course of treatment for a child.
Alder Hey Hospital said scans showed "catastrophic degradation of his brain tissue" and that further treatment was not only "futile" but also "unkind and inhumane". After his death on Saturday, the hospital released a statement offering its "heartfelt sympathy and condolences" to the family.
The couple heavily criticised medical staff, with Thomas Evans suggesting his son was a "prisoner" at the hospital and had been misdiagnosed. Hundreds of people gathered that day in the hospital and tried to storm the building.
The incident itself has caused incredible amounts of public outrage and campaigning for better treatment, with the hospital staff reportedly shocked after countless acts of abuse towards them.