On The Diary of Anne Frank (1947), Anne changes not only physically but also mentally over the course of her story.
When she first arrives to the secret annex attached to the food factory she is hopeful and optimistic; however, that optimism slowly disappears and she starts to feel lonely.
Also, although at the beginning she lacks love for her mother and feels they have nothing in common, as time goes on, their relationship changes and Anne starts to understand and appreciate her mother. At the same time, she becomes more mature and wiser, which allows her to control herself and her fears.
Moreover, Anne falls in love for the first time with Peter, a 16 year old boy that also lives hidden. She changes her mind about him as well as she changes her mind about her mother, Mrs. Van Daan and her father, who treats Anne as a child according to her words.
While hiding in the secret annex, Anne also has the chance to reflect about her life, the kind of person she is and the kind of person she wants to be when she grows up. In other words, over the course of her diary, she goes from being a child to become a young woman.