An 11-year-old boy who was on the transplant waiting list almost his whole life has finally received a kidney from a stranger who had seen his plight on social media.
Matthew Pietrzyk, who had neither of his kidneys, was constantly on dialysis and took 18 tablets a day just to stay alive.
The youngster, from Glenfield in Leicestershire, was on the UK transplant waiting list for eight years before he received his "gift of life", his family said.
A Leicestershire man, Edward Batch, 39, decided to support the family in a running event by raising awareness for organ donation through wearing a special t-shirt.
But when he heard more about Matthew's plight, he decided to sign up to become an altruistic organ donor.
He posted a message on social media saying: "I don't know if it is as easy as this so excuse my ignorance but I have a spare kidney if it helps; I'm more than willing to donate to a good cause."
The operation took place around two weeks ago at Birmingham Children's Hospital.
Matthew's mother Nicola Pietrzyk said: "Matthew has finally found his hero! It is so wonderful to be able to say that his day finally came after such a long wait.
"Matthew was antibody sensitive to 99% of the population - but we never gave up hope. It's still very early days after the operation, but Matthew is doing really well so far.
"We cannot thank his donor and family enough for this incredible gift. This is the transplant we have been waiting so long for. It will change Matthew's life and life for our whole family."
Mr Batch, who is married with three children, said it was an "honour" to help the family.
"I'm a really keen runner and saw on social media a request for people to wear the pink t-shirts for organ donation awareness," he said.
"I replied and said I was running the Leicester marathon and would be happy to wear one. It was only after that that I found out more and about Matthew's wait for a kidney transplant.
"I just felt I wanted to offer to try and help. I contacted the transplant team and said I wanted to volunteer as a living donor - I'd been prompted by Matthew's appeal but if it didn't turn out to be a suitable match I would have been a donor to another patient in need if I was suitable.
"Throughout the testing process I only had a little contact with Matthew's dad, just to keep him updated. I was very aware it was long odds that I would be a suitable match.
"But once we were told it was 100% certain the donation and transplant could go ahead, we did all meet up shortly before the operation.
"I had always believed in organ donation, but hadn't been aware of living donation.
"I'm a dad and I'd like to think if any of my children were in need someone would step forward to help and it was an honour to be able to help another family in this way."
Mrs Pietrzyk added: "Our campaign has never just been about us, there are thousands of people who need a transplant and are going through what we have.
"Organ donation is an amazing gift but not all patients will have a suitable living donor and most will get their transplants thanks to the generosity of people donating their organs after death.
"While we look forward to celebrating Matthew's transplant, we hope that hearing of his good news will prompt more people to think of the gift they could give others and join the NHS Organ Donor Register."
His family also posted the good news on Facebook. They wrote that Matthew had received "his gift of life".
They added: "Our other thanks have to go to Edward, Matthew's donor and personal hero. Without his selfless act and the support of his family this would not have been possible."
Matthew received a kidney from his mother Nicola when he was two but it was removed after just two days following complications.
When he was a baby he was diagnosed with a rare kidney condition called congenital nephrotic syndrome and doctors said Matthew would not survive childhood without a transplant.
Commenting on the news, Lisa Burnapp, lead nurse for living donation at NHS Blood and Transplant, said: "It is wonderful news that a living donor has been found for Matthew and that he and his donor are both recovering. We wish them both well.
"Living donation offers patients who are waiting for either a kidney or, less often, a liver transplant a wonderful opportunity and avoids months or even years of waiting on the national transplant list for a suitable donor.
"Most living donors are relatives or friends of recipients but, as in Matthew's case, it is also possible for people to donate to someone they have never met before. This is known as altruistic donation.
"Donating a kidney involves major surgery and when someone volunteers to donate, they undergo a series of tests to make sure it is safe and that they are donating voluntarily and the organ is suitable for the person receiving it.
"Anyone who wishes to find out more about living donation should visit www.organdonation.nhs.uk/about-donation/living-donation."