Mary Carson in Colleen McCullough’s The Thorn Birds is the polar opposite of Mariam and Laila in Khaled Hosseini’s A Thousand Splendid Suns in temperament and choices. Let’s look at this in more detail.
Mary is a hard woman who is intent upon getting what she wants but does not follow through on what she promises, even indirectly. She invites her brother, Paddy Cleary, and his family to Australia to run the ranch, implying that they will inherit it when she dies. Mary is attracted to the priest Ralph de Bricassart, and she tempts him to be disloyal to his vocation. When Mary dies, she leaves two wills, one leaving the ranch to the Clearys and one leaving the ranch to the Church. Mary thinks primarily of herself, and she acts for herself. She is a strong woman, but she uses that strength in harmful ways.
Mariam and Laila are also strong women, but their strength develops through hardship. They are both abused women who share the same husband. They must learn how to support each other and work together to survive. They are vulnerable in a way Mary Carson never is. Mariam ends up killing their husband, and she takes the punishment for it, freeing Laila to start a new life with the man she truly loves.