Two decades ago, a diminutive, peppy cartoon heroine burst onto the still nascent kids’ graphic novel scene in Babymouse: Queen of the World!, published by Random House in December 2005. The brainchild of sister-brother collaborators Jennifer L. Holm and Matthew Holm, this protagonist had a humble inception, beginning life as a sketch that author Jennifer drew on a cocktail napkin. Yet Babymouse has gone on to find fans and fame in 20 eponymous books which, together with two spinoff series, have sold more than 3.6 million copies.

To mark the character’s 20-year milestone, the publisher is releasing A Babymouse Flip Book: LOVE, a bind-up of two earlier titles, Heartbreaker and Puppy Love, now in an oversized, full-color edition for the first time, featuring colorization by cartoonist Joey Weiser.

Jennifer explained that her interest in comics dates to her childhood as the only girl in a family of five children. “My brothers were huge comics readers, and so was our dad, who was a fan of Prince Valiant and Flash Gordon,” she said. “I was reading all the usual comics and noticed that there weren’t a lot of female protagonists. Sure, there was Wonder Woman, but I was not a fan—mostly because of her skimpy costume. I longed for a girl comic-book character that I could relate to the way my brothers related to Peter Parker/Spider Man.”

Years later, after Jennifer had published multiple middle grade novels, including 1999’s Our Only May Amelia, a Newbery Honor Book (two others would follow, Penny from Heaven in 2007 and Turtle in Paradise in 2011), and Matthew had begun drawing comics, they collaborated on several single-page comics for her novel, Middle School Is Worse Than Meatloaf. “Jenni then started thinking about other ways we could make comics together,” Matthew said, and—inspired by that hastily drawn napkin sketch) the two “eventually fleshed out the idea of Babymouse as a long-form comic for kids.”

Babymouse Finds Her Niche

As the siblings began pitching the book project in 2002, they discovered that the comics publishing climate was somewhat in flux. “The traditional comics world—which included DC and Marvel—was no longer aimed at kids,” Jennifer recalled. “It was focused on producing dark, adult-themed comics like Watchmen and Batman: The Dark Knight Returns. Since I was already a published author, Matt and I felt that traditional children’s publishers might be more open to producing graphic novels for kids—although it did take some convincing.”

The project caught the attention of Shana Corey, now editorial director of Random House Graphic, who acquired Queen of the World!, which launched the Babymouse series. Asked why she was motivated to commit to this unknown graphic novel protagonist, Corey replied that she acquired Babymouse “based largely” on Jennifer’s doodle, which she called “irresistible. Babymouse’s personality and point of view leapt off the page—or the napkin. It was almost buzzing with energy, and I was sold.”

Corey was also impressed by the Holm siblings’ passion for comics for young readers. “Jenni and Matt really educated me on graphic novels and the graphic novel market,” she said. “Listening to them pitch this new series, I believed in them and their vision 100%, and was excited to follow them anywhere they wanted to go.”

Another committed Babymouse devotee is senior editor Jenna Lettice, who has edited the series for five years and worked with the collaborators to bring the original Babymouse books into a full-color format and to launch The Big Adventures of Babymouse, a larger-format color series.

Babymouse’s relatability is at the heart of her appeal, Lettice observed, describing the heroine as “a mouse of the people. She’s well-meaning, but things don’t always work out for her. She has big ideas, but they don’t always come to fruition. She has friends, but sometimes she can feel lonely. Her character is very human, and I think we all relate to that. It also helps that her flair for the dramatic, combined with Matt and Jenni’s own expansive imaginations, makes for a very cinematic reading experience.”

Babymouse’s creators are grateful for their publishing team’s support of Babymouse from the start. “We were incredibly fortunate that Shana and Random House understood the possibilities and took a chance on a new format for kids,” Jennifer said. “It was no easy feat because they had to set up an entirely new publishing pipeline to create the books as well as a pipeline to market them, as there were no shelves for graphic novels for children in bookstores or libraries at the time. Looking back, it’s kind of a miracle that it actually happened.”

Though not an out-of-the-gate commercial success, Babymouse’s debut book was embraced by librarians and was named an ALA Notable Book. Subsequent Babymouse titles followed in quick succession, and the series’16th installment, Babymouse for President, won an Eisner Award in 2013.

“It took a while for graphic novels as a whole to gain momentum with the general public,” Jennifer said. “We spent a good 10 years evangelizing to teachers, parents, and everyone and their mother that graphic novels were good for kids. It feels like things really took off some time in the 2010s, and then Babymouse was suddenly an ‘overnight’ success!”

Especially surprising for the Holm team was the level of boy readers’ enthusiasm for the series. “We had deliberately created Babymouse for girls, but boy readers absolutely embraced our messy-whiskered mouse and are some of our most rabid fans,” Jennifer noted. “They love to show up at events wearing pink shirts in her honor.”

Looking ahead, Matthew suspects that Babymouse has additional adventures in her future. “Babymouse, with her ridiculous, endless optimism in the face of total disaster, is eternally convinced that she will succeed, even though that is not always the case,” he mused. “She never quits, so I have no doubt we’ll see more stories from her.”

And Jennifer hinted at a new shared adventure ahead for her and her brother. “Matt and I have been collaborating on graphic novels and picture books for more than 25 years now—ouch, we feel old!” she said. “So, we have decided to take the crazy step of collaborating on a middle-grade novel. We’ll let you know how it goes!”

A Babymouse Flip Book: LOVE (Heartbreaker and Puppy Love) by Jennifer L. Holm, illus. by Matthew Holm. Random House Graphic, $14.99 paper Dec. 2 ISBN 979-8217115976