Between the ages of 12 and 21, people do some serious changing. Jaleel White, the actor who played Steve Urkel on Family Matters, was no different.

By the time the ABC sitcom was wrapping up, there was no getting around that White was a man. Wardrobe adjustments had to be made.

“In the final season of Family Matters, it was decided — I was not a part of any of these not sessions — it was decided that I would no longer wear jeans, because they just looked just too tight,” White said on SiriusXM’s The D.A. Show With Babchick, hosted by Damon Amendolara and Mike Babchick, while promoting his new book, Growing Up Urkel. “And if you’ll notice, on the final season of Family Matters, Steve only wears khakis.”

White wrote in his book about how much he had physically changed between when the show premiered in 1989 and when it concluded, after nine seasons, in 1998.

“I’d started as a diminutive five- foot-tall twelve-year-old kid who was now twenty-one and almost six feet tall with my dad’s long arms and broad shoulders,” White recalled. “I could no longer hide under my ‘nerd boy’ costumes. I had outgrown the character. I knew it. My cast members knew it. And the performance notes from studio and network executives encroached more and more upon my dignity.”

He gave an example of notes he received from network executives and showrunners in the eighth season: “We want to keep this character going, because everybody knows the character, but we just don’t want certain characteristics anymore. Can he lower his voice? Let’s get rid of the suspenders. Lower his pants, too. Oh, and . . . it’s getting a bit uncomfortable watching him in tight jeans. There’s a, uh . . . bulge.”

White said that it was uncomfortable for him, too.

“By the time I entered college in 1995, when the show was in its sixth season, I was peeling myself out of tight Urkel jeans like a banana.”

The actor went to the producer and told him that speaking like Urkel was putting a strain on his voice.

“In fact, maintaining the voice at this point was physically painful, and I hoped that by telling him that playing this character was now physically ailing me, it would help him to see that the show was over,” White remembered in his memoir.

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He was told that the show was making changes, and Urkel would lose the suspenders he’d been known for.

“This was the first time where I was realizing the men I benefited cleverly kept me in a box,” White said. “If Steve Urkel had been Bart Simpson, I’d still be on the air today as that character. An animated character wasn’t a real boy. But Steve Urkel was a real boy. And he had to grow up.”

Growing Up Urkel is available at bookstores.