DENVER -- If you had a sick child, how far would you go to save them?
"When we discussed it at our table, it wasn't for the world to debate," said Lisa Nash.
"I think that was the controversy, is, 'What have we created?" Jack Nash added.
What would you risk to give your child a chance at life?
"It was my baby and you know what, I was going to take care of her no matter what she had," Lisa said. "I could be killing my daughter. I signed the paper to say, 'Go do it.'"
When we first met the Nash family, they were in the middle of a very private battle. Twenty-three years ago, their daughter Molly was born with Fanconi-anemia, an extremely rare genetic disease that would eventually kill.
"Some can hear, some have thumbs, some don't have thumbs. Some have kidneys, some don't have kidneys and so its very varied. But ultimately they all develop bone marrow failure," Molly's mother, Lisa, described.
For the Nash family, that moment came when Molly was just 6 years old. Unable to find a bone marrow match, her parents would be faced with a big decision, one the world would soon weigh in on.
"When we did this, sitting at our kitchen table, this was a way to have a healthy family. This was possibly a way to protect our future children from going through what Molly went through. It was possibly a way, if it worked, to give Molly a second chance at life," Lisa Nash said.
"The whole thing was extremely cutting edge 17 years ago," said Dr. William Schoolcraft, Medical Director at the Colorado Center for Reproductive Medicine.
Dr. Schoolcraft knew if he could help Lisa and Jack Nash have a second child through IVF, he could select an embryo without the Fanconi gene. If that baby's tissue matched Molly's, doctors could then use the baby's umbilical cord blood cells to potentially save her life.
"It has the stem cells that were needed to replenish her bone marrow and regenerate the cells that she was genetically lacking. It had to come from someone whose tissue type was incredibly close to hers so her body wouldn't reject these cells," Dr. Schoolcraft said.
It worked, but suddenly the family found itself at the center of a worldwide ethical debate. There was backlash over genetic screening to have a "savior sibling" with a trait to benefit their other child. The Hollywood movie "My Sister's Keeper," was also loosely based on the Colorado family.
"If you were in my shoes, I think you'd react a whole lot differently and the people that would continue with 'I'd let my child die,' I tip my hat to them. Good for you that you could watch your child die and not do anything," Lisa said.
Fast forward 17 years and today, Molly is a thriving 23-year-old who is both driven and determined.
"I've adapted to what everybody else is doing, I do it my way," Molly Nash said.
"Molly's way" means learning to dance, ski and act in a small body twisted by an awful disease.
"I don't think I'm much different than anyone else, I just do it differently," Molly said.
She does it all with the brother who saved her by her side.
"I can't leave her if I wanted to," Adam Nash joked.
Adam is now 17 years old and both siblings admit their bond is unique.
"It kind of brings us more together than most siblings because he gave me something that I could never give him anything back for, so I kind of owe my life, literally to him," Molly said.
"I like being able to help her, it gives you a very, a very heavy purpose," Adam said.
Purpose has become a kind of mantra for the Nash family. They volunteer often and host bone marrow drives to help other people find matches. Molly's future is still somewhat uncertain but the family has learned to appreciate every day.
When asked about the decision they made 17 years ago, it is clear they have no regrets.
"I just want her to have a long, fulfilled life. I mean, I want her to outlive me, I want her to be 80, but I also don't want her to suffer. So you know, we just hope that medicine continues to advance and we stay two steps ahead of everything," Lisa Nash said.
The Nash family went on to have a third, healthy child through IVF, again selecting an embryo without the Fanconi gene.