On Sunday, the 50-year-old actress shared a throwback photo that featured the couple, along with their two children, daughter Carys, 17, and son Dylan Michael, 19, as well as Michael's older son Cameron, 41, from a previous marriage to Diandra Luker.
"We love you Michael, Happy Father's Day my love 💌🌹♥," Zeta-Jones gushed in the caption of the photo, which showed the couple's now-teenage children when they were much younger.
Meanwhile, the Fatal Attraction star, 75, shared his own heartfelt Father's Day tribute to his late father, Kirk Douglas.
"I miss him so much! Cherish your Dad while you have him #KirkDouglas #FathersDay," he wrote alongside a photo of himself with his father.
Catherine Zeta Jones, Michael Douglas and family
A post shared by Michael Douglas (@michaelkirkdouglas) on Jun 21, 2020 at 7:05am PDT
The Hollywood icon died earlier this year at 103 on Feb. 5, Michael confirmed to PEOPLE at the time.
“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 setting a standard for all of us to aspire to,” Michael wrote in a moving statement. “But to me and my brothers Joel and Peter he was simply Dad, to Catherine, a wonderful father-in-law, to his grandchildren and great grandchild their loving grandfather, and to his wife Anne, a wonderful husband.”
“Let me end with the words I told him on his last birthday and which will always remain true,” he concluded. “Dad- I love you so much and I am so proud to be your son.”
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Zeta-Jones also shared a touching tribute to her father-in-law following his death.
“To my darling Kirk, I shall love you for the rest of my life,” she wrote on Instagram, sharing a black-and-white photo giving Kirk a kiss on the cheek. “I miss you already. Sleep tight…”
A post shared by Catherine Zeta-Jones (@catherinezetajones) on Oct 3, 2019 at 2:14pm PDT
She later thanked fans for the outpouring of love and support she and her entire family received after they shared the sad news.
“Michael joins me in thanking you all for your overwhelming love, kind words and prayers since the passing of my father in law Kirk,” she wrote on social media two days after Kirk's funeral.
“My whole family appreciated every word. Love to you all ❤️,” she added.
Zeta-Jones and Michael, who have been married since 2000, welcomed an adorable maltipoo pup into their family in mid-February, a week after the death of Douglas’ father.