That night, he sees his mom and dad having sex and he hears the words tits and dicks. The kid asks, "What are those?" His parents say, "They mean hats and coats."
He sees his dad upstairs shaving and he cuts himself and yells, "Shit!" The kid asks, "What's that?" His dad replies, "It's the brand of shaving cream I'm using."
He sees his mom cutting the turkey for thanksgiving dinner and she cuts herself and screams, "FUCK!" The kid asks, "What does that mean?" She says, "It means cutting something."
Later, their relatives arrive for thanksgiving and the little kid answers the door and says, "Hey Bitches and Bastards. Hang your tits and dicks on the wall. My dad's upstairs putting shit on his face and my mom's fucking the turkey."