Catherine Zeta-Jones shares rare family photo of her son and daughter

There's no doubting who Catherine Zeta-Jones and Michael Douglas' children take after in the looks department!

The Chicago actress recently shared a rare photo of her 20-year-old son, Dylan and 17-year-old daughter, Carys — and we can't get over how grown up they are.

Taking to Instagram, the 50-year-old posted the sweet snap from their time quarantining together over summer before they headed back to their studies this week.

The photo shows Carys candidly resting her arm and chin on her brother's back, with Dylan staring into the camera.

Alongside the picture, she 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 / Getty

With Dylan usually away at Brown University and Carys at high school, The Mask of Zorro star told People magazine that the lockdown during the American summer has been a sort of family reunion.

"All of a sudden we were all back together again. And I have to say, I loved it. I really loved it," she told the publication.

Catherine and Michael have been happily married for nearly 20 years. 

When asked by ET what has made their marriage so successful, Douglas said "mutual respect." 

Michael has one son, Cameron, from a previous marriage.