MIAMI (CBSMiami) – Sam Madison was a star with the Miami Dolphins, but at home, he is a hero.
A few weeks ago, the former cornerback donated a kidney to his 11-year-old daughter.
For both, it proved to be a life-changing experience.
For nine of his twelve NFL seasons, Madison was a lock-down cornerback for the Dolphins. His athletic talent rubbed off on his daughter Kennedy, who had dreams of being an Olympic gymnast.
Last December, she noticed something odd.
"I was at gymnastics and I was swollen on my legs," she said.
When the swelling reached her abdomen, Sam took his daughter to the doctor for a checkup. He and his wife were stunned to hear that her kidneys were failing.
"You sit here and like... it's serious business," he said. "We have to do something that she gets back healthy."
"You wanna crash, but you can't because there is work to be done," said Saskia Madison, Sam's wife and Kennedy's mom.
Kennedy gave up gymnastics and went on dialysis.
"I couldn't do anything much," said Kennedy. "I had the catheter in and Dialysis was really painful for me, for other kids it's not really, but I just had trouble with it, So I was really, really upset."
Complications arose when a blood clot sent her back to the hospital.
"It was like right next to my heart and that was really scary and the shots really hurt," Kennedy said.
To keep friends and family posted on her health battle, Kennedy and her Mom launched a blog -- the Kennedy Chronicle proved to be the perfect therapy.
"I learned that sharing my feelings and sharing my experiences helps other people," said Saskia. "I thought this could, one, lighten the emotional load for Kennedy."
For Sam, life went on as a Dolphins TV analyst until he got the call that he was a perfect donor match.
"Can you do the transplant last week? That's how it was, I found out and they were like, 'we are going to do it the next week' and I was like 'ok, cool, perfect,'" Sam said.
So in early September, Sam and his daughter went under the knife. The kidney transplant happened three days before her 11th birthday. Kennedy admits it was quite a gift.
"I think he's really brave and he's very lucky and happy he did it for me and I love him for it," Kennedy said.
Since the transplant, both dad and daughter are recovering nicely. Kennedy cannot be around crowds, so she is being home-schooled.
But her precocious smile and active ambition have returned.
"Now I'm doing piano at home and I hope to do some more sports, and I want to do karate," she said. "I want to try everything."
"To be able to pass something on, it felt really good," Sam said. "I knew it was going to help her live a healthy, successful life."
"His way of showing his love, it's a gift," said Saskia. "I'm forever grateful, forever thankful and I know our daughter is."
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