Horton Hatches the Egg is a children's book written and illustrated by Theodor Geisel under the pen name Dr. Seuss and published in 1940 by Random House. The book tells the story of Horton the Elephant, who is tricked into sitting on a bird's egg while its mother, Mayzie, takes a permanent vacation to Palm Beach. Horton endures a number of hardships but persists, often stating, "I meant what I said, and I said what I meant. An elephant's faithful, one hundred percent!" Ultimately, the egg hatches, revealing an elephant-bird, a creature with a blend of Mayzie's and Horton's features.

Theodor Seuss Geisel was an American children's author and cartoonist. He is known for his work writing and illustrating more than 60 books under the pen name Dr. Seuss. His work includes many of the most popular children's books of all time, selling over 600 million copies and being translated into more than 20 languages by the time of his death.