"Epidemiological studies have shown that women with breast cancer have a younger age of menarche [the start of menstruation]," said Alderman.
"Other studies have linked early puberty to mental health issues and emotional issues," said Budzak. "They may enter into social relationships with older peers that may not be appropriate for girls their age."
Early puberty may also hit parents hard, too, as Beth Kendrick can attest.
"I was more upset than she was," said Kendrick. "She grew up so fast, and I'm also worried about all that responsibility for a girl her age."