A little boy walks up to his father on his birthday and proudly asks, “Hey, Dad! Know how old I am today?”
The father, playing along, replies, “Nope. How old?”
“Eleven!” answers the boy.
Later, the boy encounters his grandfather in the kitchen. “Hey, Grandpa!” he says, “Know how old I am today?”
“Come’ere,” the grandfather says. He pulls his grandson over, unzips his jeans and slips his hand inside the boy’s underwear. After fondling his genitals for several minutes, the grandfather withdraws his hand and says, “You’re eleven.”
“How’d you know?” asks the boy.
His grandfather says, “I heard you tell your dad earlier.”