The mother of a boy with leukaemia said three stem cell matches have been found for him after an appeal for donors.
Five-year-old Oscar Saxelby-Lee, from Worcester, was told he needed a transplant within three months of chemotherapy otherwise his chances of survival would "severely diminish".
Thousands of people joined the stem cell register in a bid to donate.
His mother, Olivia Saxelby, said it was "a million times" better than winning the lottery.
"It will save him," she said.
"Obviously there is always, always an issue where some children and some people relapse, but he has got the potential to live a happy life."
She said there would be final checks to identify the chosen donor, then Oscar will need four days of radiotherapy, expected to start on 29 April, before the transplant.
Once it is complete, he will go into protective isolation because he will be immunocompromised - meaning his immune system will be weaker and less able to fight off infections.
"It will be scary, it will be tough, but we are prepared because we know he has got the strength to pull through and we are just over the moon," she said.
Last week, Oscar was found to be free of leukaemia blast cells, meaning the transplant can go ahead.
He has been treated at Birmingham Children's Hospital for acute lymphoblastic leukaemia, which was diagnosed when he became unwell over Christmas.
Events have been run across the country encouraging thousands of people to join the register to help Oscar find a donor.
Often, a family member can donate the cells but neither of Oscar's parents was a close enough match.
"Knowing that someone out there will potentially save him is incredible," Ms Saxelby added.
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