Who is Mary Alice from A Year Down Yonder and what is their importance?

Mary Alice is fifteen years old at the beginning of the novel. Her parents are so poor that they cannot afford to keep her, and so she is shipped off to live with her Grandma in a rural town south of Chicago. Mary Alice dreads the time she will spend in the town, dismissing it as a hick town, and she dreads Grandma, whom she regards with a degree of fear and confusion.