From PEOPLE Magazine Click to enlarge
SELENA

2 MONTHS
Sick in the hospital after she was born, "this was the day we finally got her home," says her mom, Mandy.

AGE 3
"I was very shy when I was little," admits Selena.

AGE 3½
"She would always sing, dance and entertain herself," says Mandy.

AGE 5
Selena (in her Easter best) calls Grand Prairie a "plain little suburb. It was awesome."

AGE 6
"She was so fun as a kid," says her mom. "She was always happy."

AGE 11
Her favorite subject? "Biology. I love learning how everything works."

DEMI

ONE MONTH
Demi was born in New Mexico before her family moved to Texas.

6 MONTHS
Her cousins dressed her in Bulls gear, but "she's a Dallas Cowboys fan," says her mom, Dianna.

AGE 5
Even as a kindergarten student, "she was a perfectionist," says her mom.

AGE 7
Demi belts out a tune at the Texas State Cinderella Pageant in Houston.

AGE 8
"I was always singing," says Demi (performing in Las Vegas).

AGE 10
"I was very sarcastic, even at like, 4. But I was always trying to make people laugh," says Demi.