The Little Prince, Antoine de Saint-Exupéry's 1943 book, opens with a drawing its narrator made at 6. Grown-ups all say it's a hat.
It's really a boa constrictor, a huge snake, with a swallowed elephant bulging inside. Even when he draws the snake's inside, grown-ups just tell him to give up drawing.
Years later, his plane crashes in the Sahara desert, and a boy there, the little prince, sees the elephant in the drawing.