Puberty usually starts between ages 9 and 15 in boys and 8 and 13 in girls. Timing varies widely, so friends may develop sooner. In boys, puberty begins when testosterone rises. One of the first signs ...

Puberty is the process of a child's body changing to an adult body. It doesn't happen overnight, and it doesn't happen at the same age in all children. Most girls undergo puberty changes between 8 and ...