A man buys a lie detector robot that slaps people who lie. He decides to test it at dinner.
The robot slaps the son. “Okay, I went to the movies!”
The father asks, “Which one?” “Harry Potter.”
The robot slaps the son again.
The father replies, “What? When I was your age I didn’t even know what p@rn was!” The robot slaps the father.
The mom chimes in, “Haha! After all, he is your son!” The robot slaps the mother.