We know that the late Kirk Douglas had a huge impact on his children, especially Michael Douglas — and the Oscar winner once revealed the best life lessons his father taught him.

“I think his stamina and tenacity are the qualities that standout for me,” the actor, 75, exclusively told Closer Weekly. “He has taught me to always give it your best shot at whatever you take on.” The Spartacus star had reach the incredible age of 100 at the time, and his eldest son couldn’t help but gush about it.

“It is all about quality not quantity. 100 years old is certainly a milestone but the facts are what Dad has accomplished in his 100 years,” Michael said. “His 90 plus movies as a star and producer; the eleven books he’s written and published since he turned 70; the tremendous amount of public service to his country and faith.” This isn’t the first time the A-lister has touched on some wise words his father told him while alive.

Michel Douglas Kirk Douglas
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“Never give up. Never give up. Just keep working out. That’s what he says. Keep working out,” Michael told Closer at another event.

The iconic actor passed away on Wednesday, February 5. “It is with tremendous sadness that my brothers and I announce that Kirk Douglas left us today at the age of 103,” the Hollywood star wrote via Instagram. “To the world, he was a legend, an actor from the golden age of movies who lived well into his golden years, a humanitarian whose commitment to justice and the causes he believed in set a standard for all of us to aspire to.”

Michel Douglas Kirk Douglas Catherine Zeta Jones
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“But to me and my brothers Joel and Peter he was simply Dad, to Catherine [Zeta-Jones], a wonderful father-in-law, to his grandchildren and great grandchild their loving grandfather, and to his wife Anne, a wonderful husband,” he continued in his beautiful tribute.

“Kirk’s life was well lived, and he leaves a legacy in film that will endure for generations to come, and a history as a renowned philanthropist who worked to aid the public and bring peace to the planet,” Michael added. “Let me end with the words I told him on his last birthday and which will always remain true. Dad — I love you so much.”

We won’t ever forget Kirk.

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