A few days after his father died, 30-year-old C. S. Lewis received a letter from a woman who had cared for his mother during her illness and death more than two decades earlier. The woman offered her sympathy for his loss and wondered if he remembered her. “My dear Nurse Davison,” Lewis replied. “Remember you? I should think I do.”

Lewis recalled how much her presence in their home had meant to him as well as to his brother and father during a difficult time. He thanked her for her words of sympathy and said, “It is really comforting to be taken…