A mother was reading a book about animals to her 3 year old daughter.
Mother: "What does the cow say?"
Child: "Moooo!"

Mother: "Great! What does the cat say?"
Child: "Meow."

Mother: "Oh, you're so smart! What does the frog say?"
And this wide-eyed little three-year-old looked up at her mother and replied, "Bud."