Michael Douglas was mistaken for his daughter's grandfather at her graduation ceremony.

Michael Douglas

Michael Douglas

The 76-year-old star opened up about the awkward encounter with a well-wisher at the virtual high school graduation of his daughter Carys, 18 – the younger of his two children with wife Catherine Zeta-Jones.

Speaking on 'The Kelly Clarkson Show', Michael said: "We had a lovely experience. It was a virtual graduation. We couldn't actually be in the same room that she was in because of COVID protections and all of that.

"It was so wonderful and we're so proud of her, but I've got to tell you, Kelly, it's a little rough when you're going out the doors and the other parents are saying, 'Oh congratulations ... you must be so proud of your granddaughter."

The 'Fatal Attraction' star added: "I'm not gonna take it personal. They're just trying to be nice."

Michael also explained that he and Catherine are pondering empty-nest status with their son Dylan, 20, and Carys beginning their college studies.

The Hollywood star joked: "There is that moment when they're gone and they're out of the house ... and you look at each other and in the back of your mind, you're thinking, 'What are we going to talk about?'"

Catherine previously said that it was "lovely" to have her brood at home amid the coronavirus pandemic.

The 51-year-old actress said: "I must say, personally, it was lovely when we were in a vulnerable and unknowing time to have my peeps, my loved ones around.

"I had my son home from college and my daughter home from school - she goes to school in Switzerland - so we were all back in our bubble.

"And supposedly, speaking to my son, we fared better than many families. He's like, 'Mom, you don't understand. People aren't talking to each other.'... So we played lots of games."