Where most 6-year-olds run with abandon, Grayson Harris is relearning to walk without a walker.
Where most children can twist their bodies into a pretzel as they play, he is reclaiming the ability to just get on the floor.
The McDonald, Tenn., resident, the youngest of five children, has Perthes disease, a degenerative condition of the hip joint in which loss of bone mass leads to a degree of collapse of the hip joint and deformity of the ball of the femur and surface of the hip socket.
Perthes, also known as Legg-Calvé-Perthes disease, occurs in about 5.5 of 100,000 children per year.
Because many doctors are not familiar with it, children with the condition are often misdiagnosed, said Kelly Harris, Grayson's mother.
"Perthes has been related to lots of things," Dr. Shawn Standard of the Rubin Institute for Advanced Orthopedics at Sinai Hospital of Baltimore said in YouTube story on a young girl he treated for the disease, "but no one's really defined an exact cause."
And while Grayson is unfortunate in having the condition in both hips, it's not a death sentence.
"It's not forever," his mother said. "It is life-changing when it first happens, though. It will scare you to death."
Fortunately, she said, younger children have a better prognosis than older children and teenagers.
Grayson, once the most active of her children, was diagnosed in late 2009, Harris said.
"He's my little sportsman, my little daredevil," she said.
However, Grayson began to have pain in his right leg, to walk with a limp and eventually had his leg turn inward.
"He couldn't stand for long periods," said Harris. "He couldn't walk more than 25 feet before he had to stop and sit down. He was in extreme pain because it was basically bone on bone. He also had lot of stiffness. It was almost like a bad case of arthritis."
Grayson's primary physician recommended a specialist, Dr. Wendell Moses of Children's Hospital at Erlanger, who diagnosed the Perthes, recommended an anti-inflammatory to help with the pain and stiffness and, after a time of watching the disease progress, pointed the family to Standard in Baltimore.
In Baltimore, the Harrises were told they could let the femur ball joint regenerate, which would take years, or they could take an aggressive approach with surgery.
"I show [the patients] what they look like," Standard said in the online video. "I show them models. I show them pictures on other patients. ... I think if they understand what's coming, then they're not as scared."
If they let it heal on its own, it might not grow back in the socket correctly, Harris said, or if it did, it might be too big. And the time factor seemed unthinkable.
"His whole childhood [would be] gone," she said.
Grayson's treatment regimen, then, involved surgery that put six pins into his femur that keep the bone apart from the hip socket and allow new bone to grow back faster. That was to remain for four months, followed by wearing a Scottish Rite brace for four weeks and then wearing the brace for three months only at night.
Just as he was on the downhill side of the regimen, though, his left leg began to worsen. So he is having surgery on that leg in January.
"Hopefully, once that's all done," Harris said, "he'll be a normal little boy. He'll be able to run, jump and play. He may do it a little slower; he may not do it as well. And by [age] 30 to 35, he may need a hip replacement."
However, she said, Grayson's resiliency inspires her. She said she and her husband tell their son everything and encourage the doctors to talk in front of him.
"He's amazing," Harris said. "He takes it better than I would. He's resilient. He's always got a smile on his face."
She said Grayson is likely to have regular therapy and follow-up visits for years, but that is preferable to the wheelchair and walker he had been using.
"You have to keep the limbs stretched out," Harris said. "You have to keep them flexible. But right now this is working. He's doing wonderfully. His range of motion is improving."
A Facebook-based support group, doctors she can openly talk to, physical therapists to whom she can unburden herself and a supportive family have made the way easier.
"When your child's in pain," Harris said, "you want to do whatever you can to help. The care-giving is overwhelming. I never understood 24-hour care. I do now."
She said the family is fortunate to have health insurance, has benefited from yard sales to raise additional funds and a bass tournament fundraiser is scheduled later this month. In addition, an account has been set in Grayson's name at Regions Bank.
Harris also wants to create a foundation in her son's name to help other children with Perthes get the help they need.
"I want to bring Perthes awareness up," she said. "A lot of people don't know where to turn or what to do. Their [child's] childhood is being robbed. The can never get [it] back, and it just tears them up."