Della Leigh Boone always had a creature with her. Della could not wait to show her mom her new love of a creature. Her mom always ended by telling Della to "let it go."
Della somehow ended up keeping the creature until that creature decided to "let themselves go." Della always made that creature the perfect pet and found love even in the gross, slimy ones. Della even took one creature on a journey to school. That ended with a phone call and those three little words from her mom.