The mouse heroine of Whose Shoes? now raids the hat rack in Which Hat Is That? by Anna Grossnickle Hines, illus. by LeUyen Pham. ""When I wear a flippy-floppy hat,/ I dig, plant a seed,/ and weed, weed, weed./ Which hat is that?"" Readers turn the flap to find the answer (""My gardening hat!"").