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STANFORD (KTVU) -- David Diaz can finally breathe easily after he received a double-lung transplant three months ago during a rare procedure at Lucile Packard Children's Hospital in Stanford.
"Now I can run and play with my friends," said David, 9, who is about to be released from the hospital to return home to Newark in the East Bay. Helping him every step through the ordeal was his big sister, Doris, who also had to undergo the same transplant procedure a few years ago.
"I felt really bad because I went through that," she said. "I knew he would have to go through the same thing."
"She told me I would be asleep so I wasn't that worried," said David.
Both siblings suffer from cystic fibrosis. The ailment is a genetic disorder that mostly affects the lungs and can cause long-term issues that include breathing difficulties and sinus infections. There is no known cure for cystic fibrosis.
Doris, 12, says even though she survived the procedure she was afraid her brother would not because his condition was more dire.
"I was scared I would wake up and get the call that he didn't make it and that was super scary to me," she said.
Stanford is the only hospital in the western United States that performs pediatric lung transplants. Double lung transplants are so rare that Stanford has performed about 25 in the past 30 years and two of them involved David and Doris.
"Both David and Doris had some very complicated problems from very early on," said Dr. Carol Conrad, who heads Stanford's heart and lung transplant program. "Both required anti-biotics and hospitalizations. They had pretty tough lives."
The children's mother says see can finally see light at the end of what's been a long dark tunnel. And she is grateful.
"It is very important to tell (the donor's family) thank you," Corina Diaz said. "Not just for my kids but all kids."
Doctors say the siblings' transplanted lungs only hold up for so long. So it is likely both children will need second lung transplants sometime down the road.
In the meantime, however, they should be able to experience life as any other youngster.
"They should be able to run, jump and play," Conrad said.
David says he's looking forward to getting on the soccer fields with his best friends.
"I feel like a new, normal person," he said.
By KTVU reporter Rob Roth.