The Chicago actress, 50, posted the snap of her son Dylan, 20, and her daughter Carys, 17, to mark the beginning of the new school year.
Zeta-Jones wrote, "Summer officially over in our family. Today, both our young adults go back to studying. In different, unprecedented ways. I love you both... And to all kids out there. Knowledge is the key to life. So battle through. This too shall pass. (photo by mamarazzi, CZJ)."
The brother-sister duo are seen with damp hair and swimwear as Carys leans on her big brother's shoulder. And of course, fans couldn't help but notice the striking resemblance between Carys and her mom. It comes as no surprise, seeing as how they've had multiple twinning moments in the past. One person commented, "She looks like you!" Another said, "Beautiful children - they look just like their mama. God bless!"
But what really made fans do a double take was the fact that Dylan looks like a younger clone of Tom Cruise. In fact, several fans mistook Zeta-Jones's son for the Mission Impossible actor. A fan wrote, "Thought it was a young Tom Cruise at first glance." And another said, "Omg that looks like a very old photo of you and Tom Cruise!!"
The sentimental post comes three weeks after Zeta-Jones celebrated Dylan's 20th birthday. In her Instagram tribute, she wrote, "Happy Birthday to my darling son Dylan. 20 years ago today I was granted the ultimate gift that keeps on giving. You are the light of my life and I love you with every ounce of my being."
The mom shares both of her children with her husband and fellow actor, Michael Douglas. Here's hoping we see even more shots of their beautiful kids on Zeta-Jones's Instagram feed.