NEW YORK, May 8 — At a reading in New York last month, the Pulitzer Prize-winning novelist Jane Smiley faced an unruly crowd as she read from her new book, Twenty Yawns. Audience members squirmed and fidgeted, shouted out questions, and seemed to get distracted.

“The beach umbrella was flapping in the breeze,” she read. “Flap, flap, flap.”

“Look, a fly!” a little boy in a Spider-Man T-shirt yelled, swatting at a buzzing insect.

Smiley took the outbursts in stride and tried to engage an audience that consisted mostly of toddlers and their minders as she read the story, about a girl who struggles to fall asleep after a day at the beach. “Do you know how to look sleepy?” she asked. The children flopped over and pretended to snore.

For most of her career, Smiley, 66, has tried to avoid putting readers to sleep. Now, with her first picture book, she is joining a handful of well-known novelists who are aiming to reach readers so young that they probably appreciate the pictures more than the prose. A cluster of new picture books from famous writers will hit bookstores in coming months, including a lighthearted poetry collection by Calvin Trillin and a creepy, fairy-tale-like picture book in translation from the mysterious, pseudonymous Italian author Elena Ferrante, who is best known for her four-part Neapolitan series.

“Every year there are adult writers and celebrities who choose to write in the genre, but this is a particularly high-caliber group,” said Megan Tingley, the executive vice president and publisher of Little, Brown Books for Young Readers.

The current crop of picture books from literary writers is arriving at a moment when children’s literature has become a vibrant and often lucrative niche for novelists. Revenue from children’s books sales ballooned to US$1.7 billion (RM6.8 billion) in 2015 from US$1.5 billion in 2011, according to the Association of American Publishers, which tracks sales from more 1,200 publishers. Sales of adult books, by comparison, remained stagnant.

Following the blockbuster success of series like Twilight and Harry Potter, a growing number of best-selling authors have migrated into the booming market for young adult and middle-grade fiction, including James Patterson, John Grisham, Smiley and Jennifer Weiner.

Picture books, typically written for three- to seven-year-olds, could represent the next frontier for writers seeking to further expand their audiences by reaching an even younger demographic. It also may help them hook impressionable young readers — sometimes before they can even read.

Some prominent authors have turned to picture books late in their careers, motivated, in part, by the desire to write something their grandchildren could appreciate. “I tried to see things from their point of view,” said Trillin, who tested out his poems on a granddaughter. Smiley said her book had the desired effect on her granddaughter, who turns two this year: “She fell asleep.”

Others have taken up the craft as a social mission. The poet and novelist Sherman Alexie, who is publishing his first picture book, Thunder Boy Jr,” this month, said he wanted to write a picture book that featured a Native American protagonist — a rarity in children’s literature. He also hopes to reach children at the moment when they are just discovering the addictive pleasures of books.

“I always hope my book becomes the gateway drug to reading, so I was thinking, why not aim for even younger?” said Alexie, who has also published an acclaimed young-adult novel.

Once considered a stagnant category, picture books made up about 14 per cent of the market for children’s books in 2015 but accounted for nearly 40 per cent of the 100 top-selling children’s books — up from 15 per cent in 2005, according to Nielsen.

While the prose can seem deceptively simple, a well-written picture book isn’t easy to pull off.

“It’s easy to dismiss picture books because they’re short, but it’s really hard to write a meaningful and enduring text that withstands repeated readings,” Tingley said.

It took Alexie about 70 drafts before he was satisfied with Thunder Boy Jr, which is narrated by a Native American boy who wants a different name.

He wrestled with how to write convincingly in the voice of a young boy, and how to pack complex ideas about race and identity into a short, simple story.

“The difficult thing was to find a story that could hold sociopolitical meaning for the parents and the kids and blend it all together into a book that a five-year-old wants to read again and again,” said Alexie, whose book War Dances won the 2010 PEN/Faulkner Award for Fiction.

For Smiley, who has published 16 novels, including A Thousand Acres, one challenge of writing Twenty Yawns was letting the images speak for themselves and cutting down on the descriptive prose, she said. But mostly, the story was a breeze. “It doesn’t have a plot,” Smiley said. She is already working on a sequel, Twenty Bites.

At the reading last month at Bank Street Bookstore, children offered their own assessments.

“It’s a little funny book,” a boy said, as he handed Smiley a book to sign.

“Is it a little book that’s funny, or a book that’s a little funny?” she asked as he scampered off.

By then, a bookstore employee had produced a basket of teddy-bear-shaped cookies, and the impromptu literary salon broke up. — The New York Times