A kid goes up to his father and says, "Hey, Pop, know how old I am today?"
His father says, "No...how old?"
He says, "I'm eleven!"
He goes into the kitchen and says to his grandmother, "Hey, Grandma, know how old I am today?"
She says, "Come closer..."
She unzips his jeans and reaches her thin, spotted arm down into his underwear.
She fondles his genitals for a few minutes and then she says, "You're eleven."
He says, "How could you tell?"
She says, "I heard you tell your father."