Eloise was the brain-child of the multi-talented Thompson who at various points in her life was a radio personality, a vocal arranger at MGM and a popular cabaret performer. Thompson amused her friends with the voice of a little girl called Eloise, and one of those friends thought the character might make a good children's book. She lived next door to a young artist named Hilary Knight and introduced the two. It was the beginning of a close working relationship.

"We would get ideas and we would collectively paste them together," Knight says. "You know, she would talk to me and I would draw them."

Eloise has an absent mother and a cl...