An eight-year-old girl has a rare, unnamed condition that has prevented her from aging; the child is still in diapers and is about the size she was at birth.
Gabby Williams weighs only 11 pounds, and looks like an infant rather than a child, ABC News reported.
Doctors have been searching for what triggered the "off switch" in the girls development for two years, but to no avail.
The disorder is extremely rare, but has been seen before. A 29-year old Florida man has the body of a 10-year old, and a Brazilian woman, 31, looks like she's only two.
"In some people, something happens to them and the development process is retarded," medical researcher Richard F. Walker, said, according to ABC. "The rate of change in the body slows and is negligible."
"My whole career has been focused on the aging process. My fixation has been not on the consequences but the cause of it," he said.
Walker said people with the mysterious condition grow at a speed of only one-fifth the rate of a person with regular development. They also often suffer from other symptoms including "deafness, the inability to walk, eat or even speak," according to ABC.
People need "developmental inertia" in order to grow.
"Without that process we never develop," Walker said. "When we develop, all the pieces of our body come together and change and are coordinated. Otherwise, there would be chaos."
The gene associated with Gabby's developmental inertia may be damaged.
"Gabrielle hasn't changed since pretty much forever," her mother, Mary Margret Williams, told ABC. "She has gotten a little longer and we have jumped into putting her in size 3-6 month clothes instead of 0-3 months for the footies. Last time we weighed her she was up a pound to 11 pounds and she's gotten a few more haircuts."
A TLC television special will call attention to the issue.
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