Polly loves her PJs, but when Fred invites her to a party, she is at a loss as to what to wear, so she calls her friends for some help. Heap uses color to great effect in this slight story. The eponymous PJs have rosy stripes, squiggles and hearts, and Polly’s chair, slippers and walls are also pink. Fred is in grays and blues. Mia, who lends Polly a polka-dot dress for the party, favors red. Harry likes multicolored stripes—even his cat is striped. Claire has blue shoes to lend and blue glasses. But when Polly is all dressed in her borrowed finery, she sees that none of it really fits. Tears ensue, but Fred calls to remind her that it is a—wait for it—PAJAMA party, so Polly can wear what she loves best. All the friends who were willing to lend Polly stuff are at the party in their special colors. The crayon-and-acrylic illustrations are full of candy colors and cheery shapes (a lot of hearts), and it is hard to fault any story that ends with pizza. (Picture book. 4-7)