Kincaid's book Autobiography of My Mother is the story of a young girl who grows up motherless and unloved. Xuela's mom kills herself after the girl's birth. All but abandoned by her father, Xuela grows up subject to the cold and harsh hand of a laundress whom her father pays to take care of her. As she matures, Xuela learns to fend for herself, which translates in her world into an entirely selfish view of the world. She uses people for what she needs -- food, clothes, money, sex, etc., -- desperately trying to develop her sense of self worth.
Although the story is centered around Xuela, she is arguably not the main character. Xuela is the protagonist, but she is actually living out her mother's story. As Kincaid hints in her title, she is writing about Xuela's mom. Her mom killed herself shortly after the girl's birth, so Xuela is now the sole propagator of her family's inheritance. She becomes the embodiment of her mother, completely unconsciously, because she's living the life which her mom abandoned at her birth. Inheritance is the key concept of the novel. Xuela's parental inheritance is hidden from her because of her dead mother and absent father, but she still manages to gain an idea of who her mom was as she learns who she herself is. The best way to understand the person of her deceased mother, is for Xuela to discover what kind of person she is, thus embracing the secret inheritance of a child. Whether Xuela ever had the chance or not to meet her mom, she still possesses a genetic and spiritual inheritance from both of her parents which manifests in various ways in her choices and disposition.
As commonly noted in Kincaid's writing, this novel focuses on the relationship between a girl and her mom. In this case, Xuela doesn't have a mom. Deprived of this essential figure in her life, she grows up stunted in certain ways. Doubtless Kincaid's own mother played a crucial role in her own life, so she is exploring in literature the various effects on a girl's life which her mother exerts. For Xuela, she needed the love which a mom could've provided. Without it she grows up abusive and sociopathic.