The three-year-old girls' father — Michael Wagner — will donate part of his liver sometime in the next few weeks, but he can only save one of his daughters.
Johanne Wagner, the girls' mother, says she will sign up as a potential donor in a few months if another one isn't found by then.
The twins — named Binh and Phuoc — have Alagille syndrome, a genetic disorder that affects the liver, heart and other organs, and without a liver transplant the girls will die.
The parents, who have nine kids, have asked doctors to decide which of the twins will receive their father's liver because they said they cannot choose.
The couple's story, often compared to the film "Sophie's Choice", has made headlines around the world.
Michael Wagner said his wife hasn't been tested yet because she needs to be there for the kids if something goes wrong with his transplant surgery.
"She's our reserve," he said during a recent interview with The Canadian Press at the family's home in Kingston, Ont.
"Part of it is that we knew we could only do one parent at a time and that I would have to recover before she went in."
Michael underwent final testing last week at the Toronto General Hospital and is now waiting the date of the surgery, he said, which should come within the next few weeks.
The couple's story has led to a stark increase in interested donors, said Gary Levy, who runs the liver donor program at the hospital.
As of Wednesday, the hospital had received 436 applications in just a few weeks, Levy said. In the past week he's met with about a dozen candidates who want to donate their liver to one of the twin girls.
"Normally we try to restrict and push one or two through at any one time, but because of the illness status of these children, we are making exceptions," Levy said.
The hospital hopes to have a second donor for the twins lined up shortly, he said.
Levy said some of the potential donors have expressed interest in helping out many of the others on the list.
There are 227 Ontarians who need liver transplants, according to the Trillium Gift of Life Network. Last year, 84 people who needed livers died before getting one.
For the Wagners, waiting for the second donor is the toughest part.
"We're trying to keep ourselves busy," Johanne Wagner said. That's the easy part with nine children bouncing around the house.
Michael Wagner continues to struggle with the fact that he is a match for both girls, but cannot donate his liver twice.
"The cruel part of the liver is that you can only do it once," he said.
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