– Eleven-year-old Leah Williams does not perspire. Not ever. You could wrap her in a thick wool sweater and leave her out on the back porch in the middle of July and she would still return dry as a bone.

It has nothing to do with an enviable ability to remain stoic in the face of the small stuff and everything to do with an extremely rare genetic disorder called ALG13 mutation.

Her mother, Krista, was the first to notice the symptoms, which presented themselves innocently enough in the rolling eye of her infant daughter.

Doctors could not explain that symptom or others, or why Leah would continue to experience seizures almost daily for the next several years of her life.

"They weren't able to find anything different or wrong with her. They kind of just called it 'Leah Syndrome,' " Krista said.

The family adapted. Krista left her job at a pediatrician's office so that she could stay home with Leah. Her husband, Brandon, works as many overtime shifts as he can at a Wal-Mart distribution center to bridge the deficit.

Definitive answers regarding their daughter's condition remained scarce until just a few years ago, when at age 9, Leah was recommended for a gene study at Geisinger Medical Center.

Only eight other people in the world have been identified with Leah's condition.

She is the oldest. So there is no example to look toward, no diagnostic flow chart available for what her life may eventually become.

The realities of Leah's present are bracing, but more concrete. She was attending school up until last spring, but she left as her stamina and energy continued to decline.

"She used to love going outside and playing, and now she's done after 15 minutes max," Krista said.

Her nourishment is delivered entirely via a feeding tube, and her body no longer regulates its own temperature — hence the distinct lack of sweat.

Krista's mother, Cherie Buck, started a fundraising campaign for the family on gofundme.com. The goal is to not only raise enough funds to cover the cost of a new family car ­­— their current one has no air conditioning, a problem when the family needs to take Leah to her medical appointments — but to also help offset expenses incurred while Leah takes part in a study at the National Institutes of Health in Bethesda, Md.

"We were told it's the most comprehensive testing she could ever have," Krista said.

Cardiologists, pulmonologists and endocrinologists are just a small sampling of the diverse pool of medical talent that Leah will be exposed to in Bethesda.

Nobody is expecting any miracles, though. If a cure for the mutation remains out of reach, her family would settle for improving her quality of life.

"I know Leah is probably going to be more help to science than science is to Leah," Krista said.

Even if science falls short, odds are the Williams clan at large won't. Brandon said that Leah's two brothers, 17-year-old Noah and 13-year-old Elijah, have been helping to care for her since they were little boys.

They have learned to administer medicine and food with equal dexterity.

"They love Leah more than you can ever ask two little boys to love their little sister," Brandon said.