Kate and Rupert are the same size and identically dressed. When Rupert says, ""We're going to build a snowman,"" his father pauses from vacuuming to reply, ""You mean a snowperson."" But when Kate announces, ""I'm going to build a snow woman,"" her mother (who has the shortest hair in the family and is busy hanging pictures) says, ""That's a good girl""--but Rupert says, ""Nobody builds a snow woman."" Two snow-people are built, however, and apparently depart during the night, pleased to find that they are of different sexes. McKee's simple, repetitive text makes its point with deadpan humor; his cheerfully colored, cartoonlike illustrations are full of hilariously detailed artifacts and possessions that depict or refer to sex roles and relationships. There's a lot here that will appeal especially to adults, but the kids should have fun with it, too.