Hieronymus White was a know-it-all bird. He had theories about everything, from when baby birds should begin to fly (""As soon as they could, and as far and as high"") to what kind of bread to eat. But Hieronymus's arrogance, while not excusable, was understandable: The only child of immigrant parents who had left their own country to escape persecution, Hieronymus grew up with the heavy burden of trying to fulfill their dreams. But they were extremely demanding and not affectionate towards their son, and Hieronymus learned to excel in flight and in school but not how to make friends. So he was a wonder boy and a loner, and fame and fortune allowed him to surround himself with yes-men. Even his wife, Sabrina, didn't challenge Hieronymus. He was also as strict with his children, when he had time for them, as his parents had been with him. When Hieronymus's daughter, Amanda, gave birth, he looked forward to teaching his granddaughter how to fly even higher and better than he did. But the child, Selene, was born with a crippled wing. Suddenly ""he knew that no one could always be right,/And something changed inside Hieronymus White."" Hieronymus lavished on Selene all the tenderness of a lifetime. She is now grown, a writer with a child of her own, to whom she tells stories of her world-famous, wonderful grandfather, Hieronymus White. It doesn't seem possible, but it's true: In Seuss-like poetry, Moss (The Other Side of the Door, 1991, etc.) tells an amazingly profound and sophisticated story of a bird's reevaluation of life.