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But here is a brief summary.
At ages 3 & 4, Maragurite (aka "Maya) and her brother Bailey, are sent to Stamps, Arkansas, to live with their paternal grandparents. Their parents, Bailey Sr. and Vivian, feel that they are unable to care for their children. The brother and sister grow up under the tender but firm care of "Mama" and their uncle, who teach them valuable life lessons about coping with poverty and racism.
When the children are a few years older, their father comes to reclaim them, returning them to their mother, who now lives in St. Louis, Missouri. There, the children meet their eccentric extended family. But not long after their move, Maya is raped by her mother's boyfriend.
The crime colors Maya's life. For many years thereafter, she must confront the implications of her assault, and the road is not easy. She spends some time with her father (who takes her on a frightening journey to Mexico), deal with an abusive stepmother, and even runs away.
A more mature Maya takes a job in San Francisco as one of the first African-American trolley car employees. Her experiences, from innocence, to betrayal, to self-realization, are a "bildungsroman" of a "colored girl" growing up in America.