For the Simon family, it all began last September, when their 15-year-old son Scott started feeling sick.
"I'd be tired and dizzy, and I wouldn't be able to say what I was thinking," said Scott. "I just thought I had a flu or something."
But when the Fowler freshman started acting strange, his parents became concerned.
"He was almost disoriented, wasn't aware. I mean he wasn't himself," said Denise Simon, Scott's mom.
Tests revealed Scott had high levels of ammonia in his blood, a potentially life-threatening metabolic problem called hyperammonemia. It had happened before, when Scott was born. Back then, he spent two weeks in the hospital, and the problem went away.
But this time was different. Over the next three months, Scott, a three-sport athlete, went from playing football to fighting for his life.
"He just seemed to get worse and worse. He ended up on dialysis. Spent a lot of time being sedated. It ended up that there was really nothing else they could do but put him on a list for a liver transplant," said Denise.
That same September, another 15-year-old boy was also getting sick.
Jacob Brancheau of Monroe was born with a spinal birth defect called sacral agenesis and just one kidney. In 2001, his kidney failed.
After 18 months on dialysis, then 5-year-old Jacob received a kidney transplant.
It worked well for 8 years, but in September, Jacob had to go back on dialysis and on the wait list for a new kidney.
Two teenagers waiting. Two families hoping. And on Christmas morning, the call they had both been waiting for.
A nurse delivered the news to Scott's hospital room.
"She just said, 'We got a liver,'" said Denise.
Meanwhile in Monroe, the Brancheau family's Christmas plans were about to change.
"I woke up and my parents were frantic. They told me, 'We got a call, so we have to go up,'" said Jacob.
Somewhere, a family had decided to donate their loved one's organs. The liver would go to Scott. The kidney to Jacob.
As both families prepared for their son's second chance at life, they couldn't help but think about the donor's family.
"We kept remembering there was another family that was going through a whole different process. And planning a funeral," said Denise.
"You know someone had to pass away," said Kelly Brancheau, Jacob's mom. "I had a hard time that day."
It's a sadness and joy that's all too familiar for University of Michigan transplant surgeon Dr. John Magee. Magee was quickly changing his holiday plans with his wife and two young daughters to rush to the hospital.
"It certainly is a Christmas miracle. It certainly made an impression on my kids too, thinking about the spirit of Christmas and giving and helping other people," said Magee.
Both Scott's and Jacob's transplant surgeries were successful, and as it turned out, extra special.
The boys were the 999th and 1000th pediatric transplant patients at C.S. Mott Children's Hospital. It's a major milestone unmatched in Michigan.
Magee estimates he has performed about a quarter of those transplants.