Naylor continues her series featuring “Idea Girl” Sarah Simpson in a pigeon disaster that takes place outside her Chicago apartment window. Sarah hopes to keep Coo and Cuckoo, occasionally perched on her ledge, as her own pets. But she’s disappointed to discover their newly made nest in an old flower pot that rests on an opposite sill outside a neighboring apartment building. Making friends with the new Hispanic children living in the competing apartment, Sarah is determined to work something out. Her selfish concern for the birds, however, only escalates when a couple of aggressive pigeons attack their nest. Naylor masterfully creates parallel rivalry and a workable solution to both Sarah’s distress and the birds’ conflict in simple-to-read large print. Her assortment of young, multicultural city residents with Sarah leading the way will appeal to youngsters just making the transition into early chapter books. Ink-and-wash drawings add visual appeal. (Fiction. 7-9)