he catches his parents having sex and asks,"What are you doing?", to which his dad replies, "Playing poker and your mom is the wild card!"
A few days later he catches his older brother and girlfriend having sex and asks, "What are you 2 doing?"
"Playing poker and she is the wild card!", says his brother.
The next day he's in his room and his dad walks in and yells, "What are you doing?"
"Playing poker!", he says. "Then where is your wild card?"
To which he replies, "With a hand like this who needs a wild card!"