A series of entertaining vignettes about the lives of four high-spirited, globe-trotting sisters in the 1950s are meant to teach a diffident young girl about the importance of self-esteem in this well-intentioned but not particularly successful first effort. The central conceit, that lonely Cornelia finds comfort and companionship in her friendship with a lively old woman, seems entirely plausible. After all, the two share a fascination with words and Cornelia is entranced by the exotic décor of her neighbor’s lavish apartment. What strains the imagination is the notion that any 11-year-old, however sophisticated, would be intrigued by Virginia Somerset’s stories, which are decidedly adult in tone and topic. From an encounter with Picasso to the rescue of a starving Indian orphan, the Somerset sisters’ adventures are larger-than-life. Unfortunately, readers don’t find out enough about Cornelia to care about her, and the neat resolution, in which Virginia’s illness precipitates a rapprochement with Cornelia’s distant mother, seems contrived rather than heartwarming. With luck, Blume’s undeniable writing talent will be more child-friendly next time around. (Fiction. 10-12)