Michael Wagner gave part of his liver to Phuoc — one of his twin daughters who have Alagille syndrome, a genetic disorder that affects vital organs, and who would die without a liver transplant.
The Kingston, Ont., family is still waiting for a liver donor for Phuoc's sister, Binh.
The two surgeries lasted 13 hours at the Toronto General Hospital and the Hospital for Sick Children, the hospitals said in a statement.
Wagner is in good condition, while Phuoc is listed in fair condition, which means the "patient may be uncomfortable or have minor complications," but the patient has a "favourable outlook," according to the hospitals.
The twin girls' story made headlines around the world when the family said it couldn't possibly decide which daughter would receive the donation, so they left it to doctors to pick the best candidate based on medical reasons.
A post on the family Facebook page late Tuesday said Phuoc's new liver "looks great,'' but noted the next few days will be "critical."
"I could not have asked for a better way to end this long day. I am the luckiest," read a message on the Facebook page, which is managed by the girls' mother, Johanne Wagner.
The mother told The Canadian Press last week that she hadn't been tested yet because she needed to be there for the kids if something went wrong with her husband's surgery. She will get tested if another donor cannot be found.
Gary Levy, who runs the liver donor program at the Toronto General Hospital, said donors can give up to 70 per cent of their liver, which will regrow to its full size, but that a living donor can only donate once.
Levy said potential liver donations jumped sharply after news of the family's situation gained worldwide attention. In the past week he's met with about a dozen candidates and he believes he will have another donor lined up shortly.
The Wagners, who have nine kids, will hold a news conference Thursday morning to discuss the surgeries.
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