What is Claire Hudson's connection to Willy Jack in the novel, Where the Heart Is?

Claire Hudson is the librarian who works at the jail where Willy Jack is incarcerated. Since she sees her son in Willy Jack, she gives Willy Jack her son's guitar.. She sends Willy Jack to Nashville after he is released. When Willy Jack's song "The Beat of a Heart" makes it big, she files a posthumous copyright on the song in her son's name and wins the case against Willy Jack. Then, she disappears.