The Hollywood star is very different to many fellow actors though, as he isn't a fan of social media and as a result has managed to keep his private life with wife Pam Dawber and their children incredibly private.
Mark has previously opened up about their lifestyle and why so little is known about them during an interview with TV Insider.
VIDEO: Mark Harmon's Leroy Gibbs waves goodbye to NCIS
He said of their privacy: "It’s who we are. We stay home. A lot. I'm not a Twitter guy or a Facebook guy. Our sons aren’t into that either. Pam and I have both made a living in this business, and still, there’s a part of that that’s just not natural."
Mark and Pam tied the knot in 1987 and are doting parents to two sons - Sean and Ty. Pam has also opened up in the past about their decision to not share much of their personal lives with the world.
Talking to People, she said: "We're not trying to keep something secret, but if you don't want it totally exploited by the press, you have to." She added: "When you’re married, that's real life. And to go and plaster your kids…I'm sorry. I'm not for that."
Mark Harmon and his wife Pam Dawber are incredibly private
The family have still managed to maintain their low-profile despite all being in the entertainment industry. Both Mark and Pam's sons, Ty and Sean, have followed in their parents' footsteps and have pursued careers in Hollywood.
Ty is working as a screenwriter while Sean is an actor. Ever since 2008, he has appeared in NCIS as a young Leroy Jethro Gibbs in flashback episodes.
Mark and Pam are doting parents to two grown up sons
To date, he has appeared on seven of the show’s episodes, with his most recent cameo being in the 2020 episode Everything Starts Somewhere.
Gushing about his sons in a rare interview with Entertainment Tonight, Mark said of Sean: “I’m proud of him taking his work seriously and how he approaches being an actor — not just on this show.”
“I’m proud of both our boys, and they work hard at what they do and I’m proud that they get up in the morning and try to do that every day.”
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