Geronimo Stilton doesn't change drastically from book 1 to book 14. He maintains his core personality traits throughout the series:
* Timid and somewhat cowardly: He's often afraid of challenges and tends to avoid danger, but ultimately he always finds the courage to face his fears.
* Kind and compassionate: He cares deeply for his family and friends, and he always tries to help others in need.
* A curious and enthusiastic journalist: He loves exploring new places, discovering new things, and sharing his adventures with his readers.
However, Geronimo does undergo some subtle changes in the series, which might be attributed to:
* Growth and development: As the series progresses, he gains more confidence and becomes more experienced in dealing with challenges and adventures.
* Facing new situations: He encounters a variety of new environments and experiences, which helps him grow and learn new skills.
* Developing relationships: His relationships with his family, friends, and colleagues deepen and evolve over time, influencing his perspectives and actions.
Overall, Geronimo Stilton remains a relatable and beloved character throughout the series, even with his subtle changes. His core personality traits are consistent, making him a timeless and engaging protagonist for young readers.