Peyton had just finished performing in her seventh production of "The Nutcracker" when she started feeling extremely exhausted.

"I had dress rehearsals, dance, cheerleading, and seventh-grade homework, so I thought I was just really tired and sore," Peyton says.

But her mom, Carrie, knew better. "The change literally happened overnight. She lost 10 pounds in three weeks. She went from dancing in 'The Nutcracker' in December to being ridiculously tired in January," Carrie says.