Little Johhny runs into the kitchen to see his dad, says to him "Why has granny got a prawn between her legs?"
Dad returns to living room with Little Johhny to see granny fast asleep in her chair, skirt had ridden up around her waist, legs wide open and not wearing any knickers...
Dad says to Johnny, "Thats not a prawn son, thats a vagina!"
"Well it sure tastes like one, dad!" says little Johnny!!!!!!