Even young toddlers can experience erections, and often they will start to explore with what feels good to them which may include exhibiting some self-stimulatory behavior. I’m so glad you’ve reached out to us to make sure that your son grows up healthy and informed.Ĭhildren are in fact sexual beings, and even at his young age there are developmentally expected and Age-Appropriate Sexual Behaviors that you may recognize in your son. As a parent, it can be very surprising to see your 3 year old son acting sexually with his friend.