Tonbo.

Tonbo by Allen Say is a surreal and bittersweet picture book that takes readers on a journey through time. The story follows an elderly man who stumbles upon a paper airplane and begins to follow it. As he follows the airplane, the landscape changes and he encounters strangers who seem to know him. The man realizes that he is getting younger with each stranger he meets, until he eventually finds himself as a small child. The book explores the passing of time and the fragmentary nature of memory. The illustrations depict characters with various skin tones, promoting diversity and inclusivity. Recommended for ages 4-8. [Extracted from the article]