Thanks to an unseen but unusually obliging Santa, this cautionary tale of a lad discovering the hazards of even carefully phrased wishes reaches a happy resolution. On Christmas morning, Joe finds just what he asked for under the tree: a live, 12-inch-tall penguin. He only thinks that he’s ready to care for such a companion, however; after a very long romp in the snow, a cold shared bath, a breakfast of creamed herring, and a lot of cleaning up, he’s penning another polite letter to Santa, allowing as how some other gift would be okay, too. Next morning, he has a new sweater and two tickets to the zoo’s Antarctic World, which turns out to be penguin heaven. In Lewis’s digitally reworked watercolors, muted winter grays and blues unite with fuzzy-edged forms to create a chilly-looking but intimate visual tone, and Osbert’s winning, puppy-like personality comes through clearly. Salutary reading for all children campaigning for a pet. (Picture book. 7-9)