Stanley’s great-great-grandfather, Elya Yelnats, sets the family’s bad luck curse into motion by breaking his promise to Madame Zeroni. Elya doesn’t mean to hurt Madame Zeroni or ignore her request to carry her up the mountain. On the ship, he even feels bad about not fulfilling her last wish. He simply gets so caught up in his own anger and disappointment over Myra that he loses sight of his promise. Even though he doesn’t intend to cause harm, he still breaks his promise, which means Madame Zeroni never gets to drink from the stream before she dies. His moment of self-absorption has lifelong consequences for his friend and casts a curse on his descendants.
Some of Stanley’s behavior at the beginning of the novel mirrors Elya’s, demonstrating how Elya’s legacy is still alive in the Yelnats family. When he reaches Camp Green Lake, Stanley is willing to ignore Zero in order to fit in better with the other boys and have an easier time. After Zero runs away, Stanley at first continues the routine, focused on avoiding more pain for himself. This behavior is similar to how Elya, sad about Myra, focuses only on leaving Latvia to escape the pain he feels. Unlike Elya, however, Stanley decides to fulfill his obligation of friendship to Zero and go after him, even at great personal risk. Stanley’s care for Zero and willingness to look past his own bad situation leads him to carry Zero up God’s Thumb, fulfilling Madame Zeroni’s request to Elya and breaking the curse at last.