LOSTBy: Sam Usher Illustrator: Sam Usher The third title in a new quartet of enchanting picture books in which a boy and his beloved grandad discover the wonder of the natural world. The third title in this enchanting follow up quartet to Sam Usher's acclaimed seasonal books, featuring Boy and Grandad who now encounter a variety of animals and learn valuable lessons about the natural world. LOST sees the two of them setting off to search for a lost dog.