This is taken from Super Summary synopsis:
in 1980, Hattie and August bring their oldest living daughter, Cassie, to a mental institution. She has been hearing voices and has become a danger to herself and her daughter, Sala. Hattie feels overwhelmed at the thought of raising one last child but takes Sala in nonetheless. It is mentioned that Six has become a reverend, but not a holy one—he has developed a reputation as a womanizer. At church, Sala goes up to the altar to be “saved,” seeking “spiritual mercy,” but Hattie prevents her. In doing so, Hattie finds the tenderness her own children have never experienced since the twins’ death. Her purpose is to prevent Sala from feeling she is somehow wounded or broken. Hattie hopes that with Sala, she will be able to fix the mistakes she made with her own children.
The Twelve Tribes of Hattie was a critical success, with Booklist praising Mathis’s “stunning authority, clarity, and courage.” It made NPR’s list of Best Books of the Year. In 2012, the book was selected as an Oprah’s Book Club pick. Mathis works as an Assistant Professor of English and Creative Writing at the Iowa Writers’ Workshop.