For their first children's book, they chose to cast bears as the main characters, primarily because the animal held wide appeal and could be drawn easily. In the early 1960s, the Berenstains sought to enter the field of writing for young children. Nearly two dozen other books followed described by Stan as 'cartoon essays,' the titles included Marital Blitz, How To Teach Your Children About Sex Without Making A Complete Fool of Yourself and Have A Baby, My Wife Just Had A Cigar! In 1951, they published Berenstains' Baby Book, a humorous how-to aimed at adults and based on their experiences raising their infant son Leo in downtown Philadelphia. While initially working as art teachers, the Berenstains pursued a joint career in cartooning and gradually found success working together on illustrations, humorous sketches and cover art for publications including The Saturday Review of Literature, Collier's, McCall's, Good Housekeeping, and The Saturday Evening Post. After being separated during World War II, during which Stan worked for the Army as a medical illustrator and Janice worked as a riveter, they were reunited and married in 1946. Stanley Berenstain and Janice Grant met in 1941, on their first day of drawing class at the Philadelphia Museum School of Industrial Art, where they formed an immediate bond.

While enjoying decades of popularity and receiving numerous awards, the series has been criticized for its perceived saccharine tone and formulaic storytelling. The Berenstain Bears franchise has also expanded well beyond the books, encompassing two television series and a wide variety of other products and licenses. Since the 1962 debut of the first Berenstain Bears book, The Big Honey Hunt, the series has grown to over 300 titles, which have sold approximately 260 million copies in 23 languages. The books feature a family of anthropomorphic grizzly bears who generally learn a moral or safety-related lesson in the course of each story. The Berenstain Bears is a children's literature franchise created by the late Stan and Jan Berenstain and continued by their son, Mike Berenstain, who assumed partial authorship in 2002, and full authorship in 2012 following Jan's death. The Berenstain Bears: Papa (top left), Mama (top right), Brother (bottom left), Sister (bottom right), Honey (center)

Brother bear and sistwr