Mail Duck is delivering differently shaped packages to all his friends on his mail route. (Trudy likes triangles, and Harry likes hearts!) Lift the flaps to peek inside and guess what each friend received. Then head back to the post office for a big surprise: a thank-you celebration for Mail Duck planned by all his pals using the various packages they received throughout the story! Sixteen flaps and a final double-gatefold spread give readers plenty of sweet and silly details to unpack in this charming board book.