Short Riddles and Answers

Question: A man has 3 children and half of them are girls, how is this possible?

Question: I attach to your hip and I sing all day.
All I want to do is play.

Question: You throw away the outside, eat the inside, and throw away the inside.

Question: Whoever makes me can hear me, but nobody else can.

What am I?

Question: A father's child. A mother's child. no one's son.

Who am I?