Eight-and-a-half years ago, when their beautiful baby girl was born, Mr. and Mrs. Puddle couldn't agree on what to name her. So Mrs. Puddle calls her daughter Emily and Mr. Puddle calls her Ferdinanda. And everyone else? They call her Baby.

Having parents who agree to disagree does mean twice as many presents on your birthday, but it can complicate your life! When Baby's parents can't agree on what kind of dog to get, they get two—both named Sally. And one summer day, when rushing back to the city from their country house, the Puddles leave the Sallys behind. Will the Puddles agree to go back? What will become of the Sallys?