'NCIS' star Mark Harmon shares the advice his late father gave him that led him to success

Mark Harmon, star of CBS' 'NCIS,' shared the winning advice his father once gave him. (CBS)

While Mark Harmon may be best known for his role as Leroy Jethro Gibbs on the CBS drama “NCIS,” he’s had a long and illustrious career in show business. According to him, his success can be credited in large part to the advice of his father.

The star sat down with People magazine and opened up about stardom, his marriage and his more than 40-year career, which was kicked into overdrive after being named the second ever “Sexiest Man Alive” by the magazine in 1986. In the interview, the star opened up about how he’s navigated fame all these years.

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“My dad taught me, if it’s not true, don’t worry about it,” Harmon, 67, told People. “I come from working stock, and I’m proud of that. You have to get up every day and just try hard. That’s what I still wake up willing to do: try my hardest.”

Harmon’s dad is best known as famed football broadcasting icon Tom Harmon, who played in college before joining the NFL for two seasons. Mark followed in his late father’s footsteps, eventually becoming a starting quarterback for UCLA. Working hard wasn’t just an off-handed piece of advice that the star applied to show business. It was a way of life that his father made sure to teach him and his two sisters.

“Work your a-- off, and don’t let the effort show,” he says of his dad’s advice. “Also: Treat people the same, not based on who they are or what they are. Show them common kindness. Don’t be colored by their fame or profession. I don’t get all excited by people blowing smoke up my a--. You have to stay honest.”

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Now that Mark is an older man that’s found success in his own right, he’s passing the torch of advice on to another generation. He opened up to People about his advice for a long-lasting marriage.

As fans may know, Harmon has been married to “Mork & Mindy” star Pam Dwaber for 31 years. According to him, the secret to a long-lasting marriage is maturity.

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“We were both in our 30s when we got married, so hopefully the stupid stuff we did earlier,” he says. “That’s probably the closest I have to what the key is.”

The couple share two sons, Sean, 30, and Ty, 26.