5 years old sex parts awareness! Already??

by Lynn
(Chicago)

Hi

My son just turned 5 and I think he's becoming aware of his sex organs and the feel of them. Should i panic? I also have a 2 year old and they're always together.

Yesterday the older one touched his brother's privates, (with his mouth) like he was playfully biting him. I don't know what to do or think. I'm trying hard not to over think. Is this normal?

Help. Please.