A father buys a lie detector robot that slaps you when you lie.
He decides to test it out on his son at supper.
"where were you last night"
"I was at the library" *robot slaps son*

"ok I was at a friend’s house"

"doing what?" asked the father.

"watching a movie. Toy story." *robot slaps son*

"ok it was porn!" cried the son.

Father yells "what?"

When I was your age I didn’t know what porn was"

*robot Slaps the father*

The mother laughs and says "he certainly is your son"

*robot slaps the mother*