Three authors of middle grade and young adult titles transformed a panel discussion into a master class on how reality finds its way into fiction, during a wide-ranging conversation hosted by Children’s Books Boston on March 12 at Simmons University. Led by Horn Book executive editor Elissa Gershowitz, authors Liza Ketchum, Malinda Lo, and Tara Sullivan shared the extent to which they combine meticulous historical research, careful editing, and personal acumen to create realistic fiction storylines for young readers.

The author of more than a dozen books, Ketchum described the factual research that goes into her books as “a dance between fiction and nonfiction,” and called librarians indispensable guides to navigating maps and historical documents. Through various writing projects, she has incorporated newspapers from the American Antiquarian Society and the diaries of rural Vermont children from the Massachusetts Historical Society into her books. The words of those children were so powerful that Ketchum printed them and taped them to the wall above her desk as she wrote, to remind her of the ways in which children once spoke.

A self-professed “recovering academic,” Lo described research as her favorite part of writing. Like Ketchum, she commended librarians for helping her access a world of the unknown. In looking for content that can find its way into her books, the author of Ash and A Line in the Dark said, “I’m seeking out unexpected things,” with the assumption that if something is unexpected for Lo, “it will be unexpected to readers.”

One such discovery came during her research at Harvard’s Schlesinger Library, where Lo discovered that famed science fiction writer Arthur C. Clarke had penned a column for Seventeen in 1957, a year that she was researching for a book.

For Sullivan, research spawned her first book, Golden Boy, which is a story of the treatment of people with albinism in Tanzania. After reading a journal article that included the lines, “New safehouse for people with albinism in Tanzania,” Sullivan went in search of historical documents and articles before embarking on a research trip to Tanzania where she conducted extensive interviews for the book. Sullivan so thoroughly fact-checked her work that she ended up revising the train schedule times in her book to align with those in Tanzania.

In addition to their passion for factual accuracy, the authors each described a personal comfort with knowing when, where, and how to allow their fiction to depart from reality. Ketchum recounted the true story of the first person to see the Bay Area from above, a boy who accidentally took off in a hot air balloon, and said she had no qualms about transforming the boy into a girl, telling attendees, “I feel fine about it if there’s nothing to say it couldn’t happen.”

Lo described the other side of the author’s decision-making process, sharing the story of a passage in which it would have been convenient to change the name of a mayor at a particular time in San Francisco to fit her timeline. It was a decision that Lo said she quickly decided against. “I can’t make him not the mayor,” Lo said. “That would be alternate history.”

For all three authors, however, the need to establish a firm factual foundation for their work is done in the service of creating compelling fiction. The daughter of a historian, Ketchum said her work is, in part, informed by the fact that her father’s books were, “all about white guys.” Fiction, she said, creates the opportunity to enrich the stories of people who are not seen in those histories.

For Sullivan, fiction also forges a deeper connection with readers than nonfiction. “Fiction is allowing you to live an experience with a character,” Sullivan said. “Journalism is telling you something that happened.”

At the request of an audience member, the authors also explained how they approach writing about characters with whom they do not similar backgrounds. In writing Where the Great Hawk Flies, Ketchum replied that she had shared her manuscript with a woman of mixed Pequot-Caucasian heritage, the same as her protagonist.

Lo described an instance of needing to ask a Japanese-American friend for the correct term for describing a family member, in the process calling out the common prejudice that all Asian-American writers know all of the cultures of Asia. She also challenged attendees to recognize that non-white authors research white people’s backgrounds, too, telling the audience, “Every character counts. If you have no shared connection with the character then you have to do way more research, but you have to research everyone.”

The panel is one of three annual events hosted by Children’s Books Boston, a consortium that includes Simmons, the Horn Book, Candlewick Press, Charlesbridge, and Houghton Mifflin Harcourt.