Francine Pascal, the mind behind the beloved “Sweet Valley High” series of children’s books, passed away on Sunday at 92. Her daughter, Laurie Wenk-Pascal, informed The New York Times that she succumbed to lymphoma at NewYork-Presbyterian Hospital.

A native of New York City, Pascal launched the “Sweet Valley High” series in 1983. She authored the first 12 books, although the series eventually expanded to 181 books, mainly written by a team she supervised.

The “Sweet Valley” series depicted the adventures of Elizabeth and Jessica Wakefield, identical twins attending high school in the imaginary Los Angeles suburb of Sweet Valley. The series has sold over 200 million copies, demonstrating the demand for books centered on teenage girls.

‘Sweet Valley High,’ a classic for pre-teens

“‘Sweet Valley’ encapsulates the essence of high school. It’s that moment before reality sets in, when romantic ideals—sacrifice, love, loyalty, friendship—still hold true, before cynicism creeps in with adulthood,” Pascal remarked in a 1988 interview with People.

“These books have unearthed a whole demographic of young girls who previously weren’t reading. They may not all move on to War and Peace, but we have turned non-readers into readers. If they progress to Harlequin romances, so be it. At least they’re reading,” she added.

Besides the “Sweet Valley” series, Pascal contributed to “True Confessions,” “Modern Screen,” “Cosmopolitan,” and “Ladies’ Home Journal.” She also wrote for the soap opera “The Young Marrieds” and authored a nonfiction book, “The Strange Case of Patty Hearst,” in 1974.

People reported that she is survived by her two daughters, six grandchildren, and five great-grandchildren.