Little Johnny comes home from school early one day but there doesn't seem to be anyone home. He hears some noises upstairs so he goes up to investigate. Upon entering his parents room he sees his parents in bed "doing the wild thing".
He questions his dad, "Dad, what are you doing?"
"I'm playing poker."
"But whats Mom doing?"
"Oh, she's my partner."

Little Johnny makes nothing of it and leaves. He then goes into his brothers bedroom and finds him in there with his girlfriend doing the same thing.
H He questions his brother, "Brother, what are you doing?"
"I'm playing poker."
"Oh, and she's your partner?"
"Yup, you got it!"

Later that day, Little Johnny's mom walked in on him "pulling his pud".
She is horrified and asks him, "What are you doing?"
"I'm playing poker."
Of course, realizing where he hear that tries to save face by saying, "But where's your partner?"
"With a hand like this, YOU DON'T NEED A PARTNER!"