Who is Sister Louisa in the novel, Daughter of Moloka'i?

Sister Louisa promises to care for Ruth when Ruth is dropped off at the orphanage. She pays special attention to the girl and tries to raise her well all the while hoping for a loving adoptive family to take the girl. She advocates for Ruth to get to keep Only, and when she cannot get permission, Ruth lashes out in anger against Louisa. This hurts Louisa, but she also understands. When Ruth is adopted, Louisa goes and visits her on her birthday. Sister Louisa is a static character as she does not change much. She is the closest thing Ruth has to a mother figure in her earliest years. Late in her life, when Sister Louisa learns that Ruth is in Hawai’i, she asks to speak to Ruth, and she is pleased to see how she turned out.