Little, Brown Books for Young Readers is expanding its licensing relationship with Hasbro. It will launch a publishing program tied to My Little Pony, securing both print and electronic rights, and is adding more Transformers books to its roster; the new titles will start appearing in spring 2013.

With My Little Pony, Little, Brown adds another strong girls’ property to its portfolio, which already includes Mattel’s Monster High. The books are based on the My Little Pony: Friendship Is Magic TV show, airing on The Hub network; this is the first time in 20 years the property has been on television. “They did a really great job of making it feel modern and fresh,” says editorial director Erin Stein. “It’s not as super-girly as it used to be, and it has a nice inclusive message.”

In addition to 8x8s, readers, chapter books, and novelty formats, Little, Brown plans to release some titles for older fans—who identify themselves as “Bronies,” based on the fact that many of them are men—including a comprehensive guidebook to the TV show called The Elements of Harmony. “We went to Comic Con, and Pony is a huge thing right now,” Stein says. “There were adults, teens, and kids there who were all dressed up as Ponies. We realized there was an even bigger audience than we expected.”

The program also will include an original storybook, Under the Sparkling Sea by Mary Jane Begin, an author-illustrator based in Hasbro’s home state of Rhode Island. She had been working with Hasbro on the book before Little, Brown—which, coincidentally, had published Begin in the past—came on board. The book introduces a new world, called Aquastria.

Other inaugural titles include Meet the Ponies of Ponyville, a Level 1 Reader; Welcome to Equestria, a storybook; and Twilight Sparkle and the Crystal Heart Spell, the first in a new series of chapter books.

As for Transformers, the company will add several titles to its existing list, including Transformers: The Ultimate Pop-Up Universe, by paper engineer Matthew Reinhart, with whom Little, Brown had worked previously on a DC Superheroes title. The book features pop-ups that, with the pull of a tab, transform into other shapes. “We told him, the props can’t just pop, they have to change forms. We challenged him and he really came through,” says Stein, who adds, “Matthew is a huge Transformers fan. He knows all the characters, all the different versions—he knows everything.”

Little, Brown has been working with Hasbro on the Transformers property for about two years, since the last feature film, with ongoing programs including middle grade readers and tie-ins to the Transformers Prime TV show. The expansion of its license will allow it to add titles tied to the Hub animated series Transformers: Rescue Bots, which brings the franchise down to ages 3-6.