In her nimble debut, a Native American writer offers probing stories that seem as much observed from real life as created in the imagination. Several profile young girls coping with the problems of being what one character calls ``a marginal woman . . . a person of what's a supposedly fading culture trying to make a transition into what's supposed to be an improved state of affairs.'' Rare kindnesses are treasured by these characters, who find the battle for self-esteem almost overwhelmingly difficult. In ``Keeping Sacred Secrets,'' a girl raised by her much-loved father and grandmother is suddenly thrust into the care of her mother, a stranger who considers Indian ways barbaric. The eponymous protagonist of ``Katie's Flight'' learns lessons about human mortality from the death of a sparrow. In ``Music Lady'' the young, nameless narrator is encouraged in her first tentative efforts as a writer by a record store owner who understands her love and need for music. Darker pieces include a convincing first-person account of a woman's descent into psychosis and hallucination. (May)