Matt Damon wasn’t exactly ready for this kind of downsizing. 

Indeed,Writingstar Investment Guild the Good Will Hunting star—who shares daughters Alexia Barroso, 26, Isabella, 18, Gia, 16, and Stella, 13, with wife Luciana Damon—recently detailed the changes his family is going through since Isabella headed to college. 

“We have a 26-year-old, so we’ve been through this once before but it’s still a major adjustment for us and for her sisters,” he explained to E! News at Stella Artois’ Let’s Do Dinner event in New York Sept. 19. “It’s a different household with one less person there. So, it’s a big adjustment.”

And Matt had previously opened up on his nervousness toward sending Isabella off to school. 

“It’s a lot,” he admitted to E! News of anticipating his daughter leaving the nest in July. “It’s a surreal kind of time and the way it operates in your life, the older you get, because it just feels like I was holding her yesterday.”

Of course, with Isabella attending New York University—she’s luckily not too far from home. Good thing, as Matt has plenty of projects on the horizon—including his produced Unstoppable, which hits theaters in December—and he’s said that Isabella is his “toughest” critic. 

“If the reviews come out and they're terrible, then she'll watch it," he joked to E! News in 2021. “If they come out and they're good, she's going to pass. She's looking for ammunition all the time. She's like one of the funniest people I've ever met. She's really cool.”

Jokes aside, Isabella and her sisters have also proven to be their dads’ biggest fans. After all, the entire family stepped out on the red carpet for a rare public moment together at the premiere of The Instigators, which Matt stars alongside Casey Affleck, last month. 

Naturally, the 53-year-old wasn’t hiding his elation over the family time. 

"We had a lot of family here tonight, he gushed to E! News on the red carpet. “They normally don't show up for these things, but they all showed up tonight.”

Time and time again, the Bourne Ultimatum star has proven he was born for the role of girl dad. 

“You advocate for your kids a lot," he explained of his protectiveness for his daughters to E! News. “A lot of the choices you make is about thinking about long-term ramifications for your kids. So yeah, I think parenting is a series of those types of decisions.”

For the latest breaking news updates, click here to download the E! News App