Who is Miss Carrington from Crow Lake and what is their importance?

Miss Carrington is the local school teacher who teaches in the small schoolhouse that houses all the younger grades. Miss Carrington comes to the Morrison house frequently after the death of Katie's parents. Miss Carrington's first visit is one that results in Luke's decision to take custody of his siblings. Miss Carrington believes that Matt should go to university and Luke decides to give his brother this chance by taking custody of the girls instead of spending the last of the money on his own education. Later, Miss Carrington comes by supposedly to talk about Katie, but the reader never really hears the conversation. When Katie suggests later in the novel that Luke and Miss Carrington are having an affair, the reader wonders if it began much sooner than Katie suggests.