Ally Nickerson is a fictional character from the book series Fish in a Tree by Lynda Mullaly Hunt. She is a middle school student who struggles with dyslexia, which makes reading and writing challenging for her. Despite her difficulties, Ally is creative and resourceful, often using her imagination to navigate her school life. Throughout the story, Ally learns to embrace her unique strengths and gains confidence with the help of her supportive teacher, Mr. Daniels, and her friends. The narrative highlights themes of friendship, acceptance, and the importance of understanding different learning styles.