So 8 year old Johnny comes home from school one day and tells his mom that he just got laid. His mom, furious, sends him to his room.

When his dad comes home she sends him up there to punish him. His dad asks him, "What did you do this time Johnny."
To which Johnny replies, "Aw I got laid Dad."
His dad is ecstatic and congratulates him.

The following day at work he tells all his buddies about how his 8 year old son is already getting ass. When he gets home he goes up to see Johnny again and asks, "So Johnny did you get laid today?"
To which Johnny replies, "Nah Dad, my ass still hurts from yesterday."