How old am I?

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, knowhow old I am today?“She says, „Come closer…“She unzips his jeans and reaches her thin, spotted arm down into hisunderwear. 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.“