Rob Lowe's Son, a Stanford Student, Is All Grown Up & Following in His Father's Footsteps on 'The Grinder'

ET sat down with The Grinder star Rob Lowe, who chatted about his son John's guest star appearance on the upcoming Fox comedy.

It's turning into a family affair on The Grinder! ET sat down with The Grinder star Rob Lowe, who opened up about his son John's guest star appearance on the new Fox comedy.

In The Grinder, Lowe plays an actor who played a lawyer on TV. When his long-running show gets canceled, Lowe's character moves back home to work with his family, a group of real-life litigators.

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The show takes its meta theme to a whole other level when Lowe's real-life son John, 19, shows up. Lowe told ET's Ashlan Cousteau he did everything he could to dissuade his two boys from following in his footsteps.

"Here I thought I avoided all the pitfalls of raising actors," Lowe told ET's Ashlan Cousteau. "[John] is at Stanford and we're like, 'We did it! We got him into a big school!' He was one of the leading interns in stem cell research. Now he's going to be wearing makeup for a living."

Lowe's elder son, Matthew, will also have a part in the show, though acting may not be his ultimate career path. The 21-year-old college student is currently preparing for law school.

Lowe's onscreen brother, Fred Savage, gushed about his work on the show so far.

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"He's hysterical on the show," Savage told ET. "He really is just committed to getting it right."

"He and I just instantly were like real brothers and kinetically we're in sync," Lowe said. "And I was a huge fan. The Wonder Years is one of my favorite shows."

Savage landed his breakout role on the classic TV show when he was just 11, but for the past decade it's been directing shows like Modern Family and 2 Broke Girls that's paid the bills.

"I wasn't planning on acting in a show," Savage admitted.

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Not only is he acting on the show, but he's also working for Lowe, as the Golden Globe-nominated actor is also an executive producer on the show.

The Grinder premieres Sept. 29 on Fox.