In February 1999, Cody Unser, then 12 was at basketball practice when she started to have trouble breathing. She collapsed.
"I went down and touched my leg, and it was numb," she remembered. "I pinched it and nothing happened. I picked it up; it was heavy." She was terrified, she recalled.
By the afternoon of the next day, she was paralyzed from the chest down. Troy Roberts reports on the mysterious illness that attacked her, leaving her a paraplegic.
"It was terrifying," remembered her father, race car driver Al Unser Jr. "It was scary. I go out and drive 230 to 240 miles and hour; it should be me. It's not fair to grab a little girl like this who's got her whole life in front of her."
Al Unser Jr. is one of the world's top auto racers and a two-time winner of the Indianapolis 500. Her grandfather, race car legend Al Unser Sr., won the race four times.
When the illness struck, Cody was living the good life with her family in Albuquerque, N.M.
Since doctors in Albuquerque couldn't diagnose her illness, her parents brought her across the country to Johns Hopkins Hospital in Maryland. She was diagnosed with transverse myelitis, a rare syndrome that ravages spinal cord nerve cells. Most patients never fully recover. Cody's prognosis is grim.
"To be honest with you, Cody is not going to get up and walk again without assisted devices," said Dr. Doug Kerr, who created the country's only transverse myelitis center, at John's Hopkins. "She's had a severe injury."
Dr. Kerr said the syndrome is often triggered by a wide variety of common viruses, among them the flu, herpes and bacterial infection.
In most people, these viruses leave no lasting effects. But when they trigger transverse myelitis, these viruses can wreak havoc. "The immune system generated to fight off the virus in fact fights and attacks your own spinal cord," Dr. Kerr said.
"It can happen so dramatically and so quickly," he said.
Codys family believes that her illness may have been triggered by a hepatitis vaccination. Dr. Kerr would only say that the theory is worth exploring.
"It deserves looking at very very carefully," he said. "But I am not prepared to say that Cody's transverse myelitis was caused by her hepatitis."
The benefits of vaccinations, he said, far outweigh the potential risks to children.
While doctors investigated the cause of her paralysis, Cody focused on rehabilitation. She works very hard at restoring what motion and sensation she can.
"Cody is an amazing person and very very strong," said Dr. Kerr. "She really gets it. And I think what she's done is channel her frustration into saying, 'I want to help other people. I want to help myself and I want an advanced understanding of this disease.' That's how she copes, and it's a really great strategy."
Cody is using her family's famous name to raise awareness of transverse myelitis, which affects nearly 34,000 Americans. One thousand new cases are diagnosed each year.
But Cody still has difficult moments: "Of course I (sometimes) want to forget (my paralysis). But since it's part of me I can't. (It's) something like you get married, and you made that part of your life. And so I'm paralyzed, and that's part of my life."
More than a year after her paralysis, Cody is making the best of a difficult situation. With the help of family and friends, she is looking past her paralysis to promising research that may someday allow her spinal cord to heal.
Cody is confident that she will one day walk again. "I get (the confidence) from my family, my friends, and just saying 'I'm going to go there; I'm going to get there, and it's going to be that way,'" she said. "I think (attitude) is like 80 percent attitude, even more, 90 percent. You just have to make this part of your life until there comes a cure."