Child normal one week, nearly paralyzed the next

12-year-old proves to be 'fighter' while battling rare disorder

ST. JOHNS COUNTY, Fla. – A family in St. Johns County is living with what many would call a nightmare. Their pre-teen daughter was living a normal life one week, and the next, told she may never walk or talk again.

It's because of a rare, neurological syndrome that typically attacks women in their 40s. But this 12-year-old is now battling this very rare illness. Meantime, her mom is desperately seeking answers from doctors and from families -- of the few others who have been diagnosed.

Less than a year ago, Haleigh McKee was like most 11-year old girls. She would do her hair, play with makeup and clothes.

But, just a month after making a home video doing these typical things, Haleigh experienced the unthinkable. It started with a headache and double vision.

"We thought she was running a little bit of a fever from the flu. Just not feeling well," said Viki McKee, Haleigh's mom.

Later that night, the vibrant pre-teen had a seizure. Her parents rushed her to the hospital where she would remain for the next month-and-a-half.

It took more than two weeks and dozens of tests to figure out she had a very rare, neurological syndrome.

"In our situation, we were extremely lucky. That's if you want to look at it that way," Viki told News4Jax. "Because my husband and son have thyroiditis -- between that family history and the fact her brain was swelling -- that's where the diagnosis came of Hashimoto's encephalopathy."

They told the family that recovery would take anywhere from two to 25 years.

"That was absolutely devastating, because I am looking at a child in a hospital bed and at the time she couldn't walk, she couldn't talk and she couldn't eat. She could not do anything. She was incontinent and she was like an infant," Viki said.

Nine months later, Hailey uses a wheelchair. She still can't walk on her own, but she is able to talk -- just not like she used to.

"I love lipstick and shoes," Hailey told us.

The same things she loved a year ago when she made her video.

Dr. Rubina Bakerywala is a neurologist at Nemours. She is one of the many doctors treating, even researching Haleigh. Bakerywala told us this is the only case of Hashimoto's encephalopathy in North Florida.

"It's a rare and devastating disorder," Bakerywala said. "Basically, it's because of the immune system. We all have an immune system which defends us against infection. But in some people, the immune system can attack part of an organ. Like in Haleigh's case, it attacked her brain."

H.E., as it's also called, presents very differently in each person. Sometimes, it presents the way it did in Haleigh's case. Other times, it appears like dementia or psychosis. Doctors don't know for sure why it shows up suddenly, but they do know there is no cure.

"There's treatment for it by suppressing the immune system with steroids, but sometimes they need something stronger," Bakerywala said. "However, it's not preventable, and it can take years to show improvement."

With Haleigh, she's come a long way since her initial diagnosis.

"She's had to learn how to do everything all over again -- eat and talk. When she was in the hospital, she couldn't even see. She had double vision," said Viki.

But at 12 years old now, Haleigh still has a long way to go.

"I'm a fighter," Haleigh said.

When News4Jax asked her where she thinks she'll be in five years, Haleigh showed that "fighting" spirit.

"Playing soccer, volleyball, riding my bike and eating healthy," she said.

To get there, it requires her to continue multiple physical therapy appointments each week. Her mom said that her recovery is remarkable compared to what was expected. Yet, it's still hard for her to believe that her daughter's life changed like this overnight.

"One minute, you have your child with you, and the next, you don't," Viki said. "Yes, I am grateful for where we are now. I also mourn the loss of my daughter in a sense. Because she is different."

In 2009, there were only 30 known cases of Hashimoto's encephalopathy. While hundreds more exist today, it's still a medical mystery. Most of the confirmed cases are women in their 40s. But, since there is no specific test for it, and it's often diagnosed through process of elimination, many researchers and doctors believe there are hundreds of undiagnosed or misdiagnosed cases around the world.

WATCH: Mom talks about Haleigh's battle

Symptoms for H.E. differ widely but can include personality changes, aggression, headaches, paralysis, tremors, sleep and speech problems. For a list of all of the symptoms and where to turn for help, go to www.hesaonline.org.

A GoFundMe account has been set up to help with Haleigh McKee's medical expenses. You can find a direct link to it here.