The mother of a boy with leukaemia said it feels like the country is behind them, after thousands bid to be stem cell donors to find him a match.
Oscar Saxelby-Lee, from Worcester, needs a transplant within three months of chemotherapy or his chances of survival will "severely diminish".
His mother, Olivia, said the five-year-old's family was "overwhelmed" by the generosity of everyone taking part.
"Without their support, Oscar's life is at risk," she said.
"It is incredible, my thanks go out to everybody."
More than 6,000 people were swabbed at events in Worcester and more events are planned, including one at Worcester University on Thursday.
The swabs will be tested and anyone identified as a potential match will be contacted.
Often, a close family member can donate the cells but neither of Oscar's parents was a close enough match.
The Pitmaston Primary pupil is being treated at Birmingham Children's Hospital for acute lymphoblastic leukaemia, which was diagnosed after he became unwell over Christmas.
But his cancer needs to be in remission before he can have the transplant.
His mother said tests showed three chemotherapy treatments had not worked.
He is undergoing a fourth, and will know the outcome in a fortnight.
"He is a strong warrior, but, at the same time, options are getting lesser and lesser for him at the moment," she said.
"Things are unforeseen but, at the same time, we have a lot of hope the chemotherapy will help him into remission and into transplant where he needs to be."
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