Little Johnny Grandma's House Joke

Everyone was seated around the table as the food was being served. When Little Johinny recieved his plate he started eating right away. "Johnny, wait until we've said our prayer," his mother reminded him. "I don't have to," Johnny replied. "Of course you do," his mother insisted. "We say a prayer before eating at our house." So Johnny said, "Thats at our house, but this is Grandma's house, and she knows how to cook."