As readers of Regan's Monsters in the Attic (1995) already know, Rilla Harmony Earth (formerly Rilla Pinowski) receives a different monster in the mail every month. Usually the monsters are stuffed animals, but sometimes, when the cosmic forces line up just right, they come to life. September's offering, a bespectacled owl, arrives laughing. Concealing the live monsters from her family is never easy for Rilla, and feeding them can be a problem if they prefer junk food, because Rilla's health-conscious mother runs a very New Age bed-and-breakfast. Owl is easier to care for than the others; he eats paper and comprehends the words on any print material he consumes. Owl is a big help with homework, but when he eats part of a computer manual, he goes wild surfing the Internet. Rilla's problems are compounded when the July and August monsters come alive, but monster management isn't the only thing on her mind: She wants to use the Internet to find her missing father, and she goes out on her first date. Regan skillfully mixes fantasy with realistic 13-year-old behavior, adding a lot of tongue-in-cheek humor about Rilla's politically correct family. Along the way, Sweet provides funny black-and-white illustrations. This offering in the series puts middle-grade readers right into Rilla's shoes, and it couldn't be a better fit.