Bella J. Dark, who lives in Weymouth, Dorset, England, is the author and illustrator of The Lost Cat, a cautionary tale about an animal that indulges its curiosity and then depends on its mother for safety.

Bella's parents encouraged her to keep her promise that she was going to write a book someday but didn't think that that day would be right around the corner. A year after making the announcement, Bella got her book published, by Ginger Fyre Press, a new imprint of Dorset-based Veneficia Publications. Bella's mother, Chelsie Syme, helped with the proofreading and in dealings with the publisher.

As of June 2022, Bella's book has sold 2,000 copies. The Guinness World Records people issued Bella a certificate confirming her as the youngest published female author. The record-holder is Thanuwana Serasinghe of Sri Lanka, who published a book when he was 4, in 2017.

The cat in the book is named Snowy. Bella is planning a sequel, tentatively titled Snowy's Birthday Party. Time will tell whether she again enlists her older sister, Lacie, to help with the illustrations.