Assuming you have a good relationship with your parents, they've probably done a lot of nice things for you. Made you dinner. Put clothes on your back. Gave you presents. Said they love you.
But how about - gave you a lung. Or better yet, two lungs.
Well, a mother and father in Germany have done it - they each gave their 12-year-old son a lung, to try to save his life. The boy's name is Marius and he suffers from cystic fibrosis.
Over time, he became so sick he needed both a ventilation machine and a heart-lung machine to help him breathe. He was waiting for an organ donor, but things got so bad, he couldn't wait any more.
So, his parents decided to each donate a lung to save their son. And as luck would have it, both his mom Anja and his dad Lars had compatible blood types.
Doctors say the transplant was Marius' last chance, and that operating on living donors is only a last resort. Here's how it happened.
Surgeons operated on Marius, his mom and his dad at the same time in three different operating rooms. They removed a lung from each parent and transplanted them into Marius.
The actual transplant surgery took six hours, and Marius had to stay in hospital for 5 months before he was well enough to go home.
Doctors say his immune system is still weak, and he still has to take a series of drugs because his cystic fibrosis isn't gone. So, there's still a chance his new lungs could be affected.
But overall, they say his quality of life is a lot better. He can't go to school yet, but he can ride his bike and play soccer.
With cystic fibrosis, the body produces mucus that is thicker than normal. Over time, it fills the lungs, making it difficult and eventually impossible for the person to breathe.
According to Cystic Fibrosis Canada, one person dies from cystic fibrosis in this country each week. Of the 40 patients who died in 2010, half were under 26 years old. One in every 3,600 children born in Canada has the condition.
In the 1960's, most children with cystic fibrosis died before they got to kindergarten. Today, half of all Canadians with cystic fibrosis are expected to live into their 40s and beyond.
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