An American man has travelled thousands of miles to give one of his kidneys to his cousin in England.
John Williamson, 42, from Michigan, is recovering in hospital in Bristol, after having major surgery to give a kidney to Andy Williamson, 44.
John helped after reading on Facebook about his cousin, who has polycystic kidney disease.
Andy, from Ashburton, Devon, had to have dialysis every day after a donated kidney failed in 2011.
John said: "It was just something I felt I wanted to do.
"I have two young daughters, and I know what energy it takes to look after them.
"I wanted to be able to help Andy get a new lease of life, not just for himself, but for his family, and his daughter Doro in particular."
The pair met earlier this year, for the first time since they were children, when John came to England to have tests to see if he was suitable to become a donor for Andy.
The doctors gave the go-ahead, and now both men are recovering at Southmead Hospital in Bristol, where both the operation to remove John's kidney, and the transplant to give it to Andy, were carried out.
The operation to take out John's kidney - called a nephrectomy - was carried out by surgeon Mr Najib Kadi using keyhole surgery.
It was a painstaking process, which took three hours.
Mr Kadi said: "This is complex surgery, you need to handle the kidney very carefully because it is being used for transplantation.
"The donors are very precious, like any other patient, but particularly because they are people who are putting themselves through surgery to make someone else better."
John's kidney, once removed, was placed in special chemicals and ice and put in a cold bag while a different surgical team, led by Andrew Weale, started work on preparing Andy for his transplant.
Once Andy's body was ready, Mr Weale attached the kidney.
"It's pretty amazing that at the start of this morning this kidney was in another person," he said.
"It's been removed and has been on ice for an hour and a half and now we're putting it into his cousin.
"The kidney has gone a lovely pink colour, and it's producing urine already. It's wonderful."
The unusual transatlantic kidney donation was managed by Kay Hamilton, the living donor co-ordinator at Southmead Hospital.
She says the sacrifice John has made, coming abroad for the operation, has been amazing.
"It's fantastic. He's come all this way to do this; they're obviously very close as cousins, and it's even more fantastic because they've got an identical tissue type match, so it couldn't be a better kidney for Andy. "
Both men are now recovering.
So how does John feel at this point?
"As expected I'm a little sore, but in good spirits; I'm glad I did it.
"Andy looks great, he has some recovery to do but he'll be in tip top shape before long. I'm confident I will recover properly.
"I feel it has been very worthwhile and the benefits far outweigh the risks."
Andy is blown away by what John has done, and says it highlights the need for more living donors to come forward.
"Over three hundred people die every year while waiting for transplants; these are needless deaths, and what I am increasingly realising is that an organ donation has a much wider impact than just for the recipient.
"It's also about the lives of their families and the people around them. It really is a tremendous gift."