What is the theme in Daughters of the House by Michele Roberts?

Sin and purgatory is another theme in the book. As Antoinette becomes more and more ill, Thérèse turns increasingly to religion to deal with her grief and loss. Thérèse believes firmly in the teachings of the church, though her beliefs are sometimes skewed because she is just out of childhood. One example of this is her admission of praying for the conversion of Jewish souls and the way she blames the Jews for Jesus' persecution, saying that they were "just as bad as the communists" (66). As Antoinette becomes more ill, Thérèse begins to deprive herself of comforts. She secretly says prayers at many times in the day, never knowing when she will have said enough to provide a safe passage for her mother through purgatory.