A rare metabolic disease, S-adenosylhomocysteine hydrolase deficiency, made proteins poisonous to three-year-old Kennedy Stevenson, according to ABC News.

According to Kennedy's mother, Kennedy is "one of eight in the world diagnosed, one of six living with her disease," and the first person in the world to have a hopefully-life saving surgery performed.

Donya McCoy, Kennedy's mother, turned to Facebook to ask for a liver donor for her daughter. Thanks to an old high school friend of McCoy's, Kennedy will get her first bite of turkey on Thanksgiving this year.

"She just ate a chicken finger for the first time ever," McCoy told ABC News. McCoy said her daughter wasn't entirely sold on the chicken, but chocolate milk was a big hit.

"Her eyes got big and she just kept sucking the straw," McCoy told ABC News. "She didn't want to stop."

Kennedy had previously been on a diet "stricter than vegan," McCoy told ABC News, to prevent the enzyme deficiency from causing a buildup of toxic substances. S-adenosylhomocysteine hydrolase deficiency leads to neurological deterioration as time goes on.

Kennedy will remain in Children's Hospital of Pittsburgh, where she had her surgery and she will stay as an inpatient "through the holidays," according to ABC News.

"She can now have turkey and stuffing," McCoy told ABC News. "It's just going to be really special that she can eat a Thanksgiving dinner."

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