Doctors at the Stollery Children's Hospital say a donor needs to be found for Harrison Aikman of Regina within three days.
Harrison is in acute liver failure and tops the waiting list in North America.
His aunt, Norma Rae Chapman, says one month ago Harrison was active and full of energy.
Then one day he came home from school tired with yellow colouring and darkened eyes.
Medical tests have ruled out many of the common causes of liver failure.
"Everything changes within three weeks when all of a sudden, there's this little boy who won't make it without a donor," Chapman said.
"They couldn't seem to find any rhyme or reason for what was happening, but he seemed to be getting weaker every day."
Harrison's condition has become worse since he was taken to the Edmonton hospital, she said.
"It's quite devastating. It's quite surreal actually," Chapman said on behalf of the boy's relatives who are waiting with him in Edmonton.
Chapman says doctors still aren't completely sure what caused his liver failure, but believe it may have been a condition that was lying dormant since he was born.
He needs a liver from another child who has died or half of an adult organ.
His other aunt is on her way to Edmonton to see if she is a match. His mother could also donate part of her liver, but doctors have said that is a last resort because parents need to be there for children who are in recovery.
"Minute by minute you're waiting for the call," said Chapman, who added she now realizes how many people need organ donors.
"Every child on this ward is waiting for an organ and it just changes your whole view of life."
Helene Campbell, a young woman from Ottawa who received a double-lung transplant in April, has captured attention around the world with a similar plea. She has become a poster child for organ donations, driven in part by her appearances on the TV talk show hosted by Ellen DeGeneres and by an endorsement from pop idol Justin Bieber.
(CJME, The Canadian Press)
In addition to a deceased liver of a child or half of an adult's, Harrison's best hope is a living liver donation. A portion of an adult's liver can be transplanted into him. Donor's must have a blood type of O- or O+. The donor's liver will regenerate to its regular size relatively quickly.
Anyone wishing to donate is urged to email Toni Chow at Stollerly's Hospital in Edmonton email@example.com
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