What is "a lil' birdie"? Does it really mean a bird?
Great question. This is a version of a popular idiom (a little bird told me). It is used to say that the speaker knows something but prefers to keep the identity of the person who told them a secret. It is not referring to a real bird. Ex: A little bird told me we have an exam today. Ex: A lil birdie told me you're thinking of quitting.