A toddler who received a life-saving bone marrow donation from his brave sister has tragically died from an unrelated illness, it emerged today.
Oliver Boyd underwent a bone marrow transplant aged two-and-a-half months in a bid to combat a rare and severe immune deficiency called Omenn syndrome.
His then nine-year-old sister, Abigail, was a 100 per cent perfect gene match and without the transplant Oliver would have died before he reached his first birthday.

But in a cruel twist of fate, Oliver has now died from unrelated lung problems at the age of two.
His devastated father Paul said: “He had a great quality to him, whether he was in the hospital or at home.
“He has made us all very proud because he never gave up.”
Mum Heather added: “He never complained once. He was always smiling and happy.”
Oliver, of Auchmithie, Angus, Scotland, was born in July 2011 but it was quickly realised his immune system was incredibly weak and his parents weren’t allowed to even kiss him for nearly eight months.
After almost a year in Newcastle’s Great North Children’s Hospital, Oliver was eventually allowed home.
He spent most of his life indoors to prevent infection and receive oxygen, but he was a happy little boy.
But a problem with his lungs emerged just after New Year which was due to an uncontrollable level of carbon dioxide building up in his blood.
Just days later, on January 10, Oliver lost his battle in hospital surrounded by his family.
Heather said: “When he was fighting, he was still happy, but his lungs just gave up.
“On the Wednesday we got concerned about his oxygen requirement as it had gone up.
“We took him to the hospital in Newcastle and we were all in agreement that something wasn’t right.
“They gave him intravenous steroids to see if that would help but his blood tests showed that his carbon dioxide levels were very high.
“They admitted us on the Thursday and then they said that he did not have long left.
“They said his blood gas was at an uncontrollable level.”
Heather admitted Oliver’s life-saving sister Abigail was devastated at the loss of her younger brother
She said: “Abigail was very protective of him and they were very close together – he called her Aba.”