And, as The Early Show national correspondent Jon Frankel discovers, a little girl in Illinois is leading the way.
Like most 4 year olds, Jessica Hill gets her hands into everything. She loves blocks and is building a future nobody thought possible.
"They told me she would never walk, she'd never run, she'd never crawl," said Jessica's mother, Leann. "You know, that was what our life was going to entail was a child who was paralyzed from the waist down and we would have to deal with it."
Jessica was born nine weeks premature, weighing barely three pounds. She had meningitis and an infection that led to water on the brain. One lung collapsed and the other had a hole.
"She was born with an infection that caused a problem in her brain that basically caused a stroke in her spinal cord … so she was paralyzed about nipple line down," said Dr. John McDonald, a neurologist at Washington University Hospital.
McDonald has lots of experience treating adults with spinal cord injuries, including actor Christopher Reeve. Jessica became his first pediatric patient two years ago.
"He said, 'Basically what I'm going to tell you is … if you do the things you're supposed to do, the treadmill, the bike, repetitive motion over and over and over … I don't see why she couldn't make a full recovery,'" said Leann. "Walking without braces."
With braces and a special harness, Jessica began working on a treadmill.
Leann says her daughter made a big breakthrough on New Year's Eve this past year.
"She crawled for the first time … that would be the biggest breakthrough," recalled Leann. "I think she realized, just from that night, right then, 'I've done something great and this is pretty cool and everybody likes it so I'm going to do it some more.'"
Jessica, at times, looks like an athlete in training. She's on a treadmill, bike or just playing ball from five to seven times a day.
"I think it's still play [for her]. We do it and then she'll want to go back and do some more," Jessica's father, Kevin, explained.
"I think I keep raising the bar, but she's the one making me raise the bar," said Leann. "She keeps exceeding every goal that I set for her in my mind … She knows that doing her bike and doing her treadmill will help her walk."
Jessica has endured nine surgeries, but remains a playful and happy little girl for whom anything is possible.
"The prediction should be that she will walk again," said McDonald. "And there's nothing that should stand in the way of that."
The doctors says that with the progress Jessica is making, she should be able to run and look like a normal child.
"He says that she will be walking by her fifth birthday," said Leann. "He's been right on everything else. I hope he's right on this one."
Jessica's mother says she makes sure to let her daughter dictate the pace of her therapy. If Jessica wants to do her exercises, it's fine with mom. If she doesn't want to perform the task, it's also fine with her. Leann says she won't force the issue, but keeping it fun is key.