It's almost Cinderella-in-1913-Brooklyn--because 13-year-old Gertie Warshefsky is treated like a slavey by her two horrid young aunts and her mean grandmother, and constantly told that her institutionalized mother is crazy, that her departed father has deserted her. It's also totally without color or flavor as a depiction of a very particular milieu. But in addition to some story values--new boarder Mr. Neufeld is a reader, like Gertie; he acquaints her with the Bible, and especially with the inspiring story of Queen Esther; she gets to play Esther in a local Purim celebration--there are two vivid, lacerating scenes at the mental institution where Gertie's mother is confined. And in the second of the two Gertie comes to accept her mother's retreat into early childhood, and treats her tenderly--like a small child. But the very fact that one is impelled to break the book down into its components--rather than to relate what occurs--is a measure of its weakness. The ending, indeed, is all-too-pat: Mr. Neufeld departs, after Gertie has only been ""Queen for a day""--but he sends money for her keep, to ease the pressure on her; her grandmother turns out--abruptly--not to be altogether uncaring; and her father, contacted by Mr. Neufeld, also conveys his continuing concern. The mental-hospital element alone is both sensitively handled and altogether convincing.