Who is Indian Woman from Mrs. Mike the Story of Katherine Mary Flannigan and what is their importance?

She is the fifteen-year-old Indian girl who Katherine brings home from the Mission to help with the baby and housework. Oh-Be-Joyful is in love with Jonathan, a proud and tenacious Indian of whom the sisters at the Mission do not approve. The sisters want to keep Oh-Be-Joyful away from Jonathan because they do not want for her to end up a klooch. Klooch simply means Indian woman.