The Contagion star is living in a Dublin suburb where he was filming new Ridley Scott movie The Last Duel when the country went into lockdown.
Damon told Irish radio station Spin 1038: “Our oldest daughter is in college, she’s in New York City. She had Covid really early on, along with her roommates and got through it fine.”
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The 49-year-old action star is step-father to 20-year-old Alexia, his wife Luciana Barroso’s daughter with ex-husband Arbello Barroso.
Damon, Luciana and their daughters Isabella, Gia and Stella are all living in lockdown near Dublin.
He said: “Everybody’s okay.
"I think we’ve all got the message now, everybody’s doing the isolation and the social distancing and hand washing, everything we can to mitigate this."
"We’re going to go back to Los Angeles and she’s (Alexia) going to come out so we’ll all be together and figure out what the heck we’re going to do. It’s such an odd limbo that we’re all in."
Damon admitted he was “a little worried” about returning to the US.
He said: “We don’t have adequate testing so there’s going to be another surge it looks like back home. There’s all these areas in America that it hadn’t really penetrated and now, y’know…"
Damon met his Argentine wife in Miami in 2003. They married in 2005 and live in Los Angeles with their daughters.
The Last Duel co-stars Adam Driver, Benn Affleck and Jodie Comer.