Once upon a time three little horses grazed together in a meadow full of lovely, thick grass. Wherever one went, the other two followed. One day they met an artist named Peter, who was so happy to have found them. "We shall have good times together, you'll see," he told the three little horses.

First introduced in 1958, these dear characters were Piet Worm's neighbors. The three little horses played all day long in a meadow near his house. Watching them and learning to know and love them sparked the idea for this book.