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Transplant girl Phoebe Pace, 5, goes for gold again
29 July 2015 Last updated at 04:05 BST
Every day, three patients in the UK die because they cannot get the donor organ they need, according to NHS figures.
To help raise awareness of the problem, a five-year-old from Gateshead will be competing in the annual British Transplant Games on Tyneside next week.
Phoebe Pace underwent an emergency liver transplant when she was a toddler. Months later she took part in her first race – and has so far clocked up 17 running medals in her short life.
Look North’s Sharuna Sagar has been to meet the little girl who is going for gold.