Ruth Anne "Bone" Boatwright is born out of wedlock to fifteen-year-old Anney and has "ILLEGITIMATE" stamped on her birth certificate. Anney tries multiple times to get a new birth certificate without the stamp, but with no success.
The extended Boatwright clan is a tough but poor bunch living in Greenville County, South Carolina. Anney works long hours in a diner to support her daughters after her first husband dies in a car accident.
Anney's brother introduces her to Glen Waddell, the youngest and least successful son of a dairy owner. Over the course of a few years, Anney allows herself to trust him and let him be a father to her daughters.
When Anney gets pregnant with Glen's child soon after they are engaged, Glen is elated. But, as she's giving birth, Glen molests Bone in the car in the hospital parking lot. Anney's child is stillborn, and she can't have any more children.
Glen's temper, already volatile, becomes even worse, and he can't keep a job. The family is almost always strapped for cash in, and they're constantly moving.
Glen starts physically and sexually abusing Bone on a regular basis, dragging her into the bathroom for minor offenses and beating her savagely with a belt.
Outside of her home, Bone has a loving extended family made up primarily of three maternal aunts (Alma, Ruth, and Raylene), three uncles who are regularly in jail for fighting (Earle, Beau, and Nevil), her tough ol' Granny, and an ever-increasing number of cousins. They offer her various kinds of sanctuary from the unhappiness of her home life.
As Bone grows older, she goes through various phases: moving from school to school, being called "trash," befriending an albino outcast girl named Shannon Pearl, temporarily finding religion through gospel music, stealing, breaking into a store, taking care of her dying aunt, and starting to go through puberty. Her life, though, is still threaded through with abuse from Glen.
After Bone ends up in the hospital, Anney leaves Glen until he swears never to hurt Bone again. The abuse starts up again, and Bone becomes withdrawn and angry. She doesn't tell anyone about it for fear of upsetting Anney.
On the day before Aunt Ruth's funeral, Glen beats Bone particularly savagely. The next day, after the funeral, Bone gets drunk for the first time. Her Aunt Raylene finds her in the bathroom and sees the blood on her legs. She shows Bone's uncles, and they beat up Glen.
Anney leaves Glen again, but Bone blames herself for the breaking up the family and for Anney's quiet anger. Bone tells her mother that she will never live with Glen again. Anney understands but is at a loss as to what to do.
While Bone is staying with her Aunt Alma, who recently suffered a breakdown, Glen shows up while Bone is alone in the house. He blames her for the fact that Anney left him, and he violently beats and rapes her.
Anney walks in and starts screaming and throwing things at Glen. Then she drags Bone to her car while Glen begs for forgiveness. However, she ends up pressing Glen's face to her stomach and crying.
When Bone gets out of the hospital, no one knows where Anney has gone. While Bone is staying with her aunt Raylene, Anney shows up with a birth certificate for Bone that doesn't have "ILLEGITIMATE" stamped across the bottom. She tells Bone that she loves her and leaves. Bone doesn't understand Anney's actions. She wonders what kind of person Anney was before she had Bone, but she knows what kind of person she herself is going to be when she grows up.