Henry Winkler.Photo:Michelle Groskopf

Michelle Groskopf
Henry Winklermay be known as one of the most genial actors in Hollywood, but during the height of hisHappy Daysfame, he harbored secret pain few knew about.“I spent most of my adult life being frightened, on the outside looking like I had it together and mostly being anxious,” Winkler, 77, tells PEOPLE in this week’s issue, out Friday.Born in New York to German Jewish parents who escaped the Nazis in 1939, Winkler calls his upbringing severe. In school, he struggled with reading and comprehension. “I was a terrible student,” he writes in his new memoirBeing Henry: The Fonz…and Beyond.

Celadon Books
Winkler turned to humor to mask his struggles, eventually using his improv gifts to leapfrog from the Yale School of Drama to Hollywood, where a walk-on part onThe Mary Tyler Moore Showled to a history-making audition forHappy Days.
At the height of his Fonzie fame, Winkler marriedhis wife Stacey, whose young son Jed would begin displaying cognitive issues at school. Eventually the couple took Jed to an occupational therapist who diagnosed him with dyslexia. A light went on for Winkler.“In third grade he had to write a report and couldn’t do it,” Winkler tells PEOPLE. “I said to him everything that was said to me: ‘Go back to your room. You’re being lazy. Live up to your potential. You’re so verbal.’ I then had him tested and we read everything they said. I went, ‘Oh my God, Stacey, this is me. I have something with a name.'"
Henry Winkler, Stacey Winkler and their three children Max, Zoe and Jed.Tibrina Hobson/Getty

Tibrina Hobson/Getty
Winkler’s other two children with Stacey, Max, 40, and Zoe, 43, would eventually be diagnosed with the learning disorder, too. “It’s hereditary,” says Winkler, who went on to launch secondary careers as a Hollywood producer (he’s produced the mid-1980’s hitMacGyver) and a prolific children’s book author (his latest book,Detective Duck: The Case of the Strange Splash, is out now).Now, he’s finally written his life story. “My son Max said to me over the years, ‘Dad, you got to write a memoir. You’ve got so many stories.’ I said, ‘I’m dyslexic. I’m not writing a memoir.’ I dismissed it out of hand. There are so many things that I have done now that I have dismissed out of hand and boom, they became a really important part of my life,” says the star.
Ron Howard (left) and Henry Winkler in ‘Happy Days’.ABC Photo Archives/Disney General Entertainment Content via Getty

ABC Photo Archives/Disney General Entertainment Content via Getty
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Being Henry: The Fonz…and Beyondhits bookshelves on Oct. 31.
source: people.com