After her mother's death in 1953, fifth-grader Mary Brooke comes to share the family home with Aunt Olive, who's been living there alone. Her aunt seems cold and aloof, in contrast to her fun-loving mother, and Mary Brooke dreams that her unknown father will finally appear. Meanwhile, she's too reserved to make friends, but is intrigued by a sealed-off tower room, once her grandfather's. Finding a concealed entrance, she secretly fixes up the room, working in the afternoons before her aunt gets home. When a girl at school taunts her with the devastating news that her mother died after an illegal abortion, Mary Brooke takes refuge in the room. She hides there all night before, hearing her aunt's despairing sobs at her absence, she comes out; various mysteries are explained, and Mary Brooke discovers how much she and Aunt Olive have in common. This well-crafted novel has all the appeal of a juvenile gothic, plus much more: Mary Brooke and the reader realize together just how selfish, feckless, and promiscuous her mother was; a friendship with the boy next door, which begins when Mary Brooke finds him mourning his cat, adds a nice dimension. It doesn't quite ring true that the other girl knows about the abortion, or that Aunt Olive doesn't know of the second entrance into the tower; but those are small flaws in an unusually engaging story with a real heartwarmer of a conclusion. (Fiction. 9-12)