Matt Damon opened up about his family in a new interview, in which he shared that his stepdaughter Alexia, "just got her license" -- get more updates here. Credit: Mike Marsland/WireImage.com

They grow up so fast! Matt Damon, who's generally pretty tight-lipped about his personal life, opened up about his family in a new interview with USA Today, revealing snippets about his kids with wife Luciana Barroso.

"My oldest daughter just got her license yesterday," the Martian actor, 44, told the paper with what the interviewer described as a "proud smile" on his face. (Damon's oldest child is actually his stepdaughter, Alexia Barroso, his wife's kid from a previous marriage.) According to USA Today, the Oscar winner even taught Alexia how to drive.

"She would drive last year just to school every morning," he said of his teen. "We'd get in the car and drive."

Damon, who shares three other girls, Isabella, 9, Gia, 7, and Stella, 4, with his wife of nearly 10 years Barroso, typically prefers to keep his children out of the spotlight.

"I attribute a lot of it to luck," Damon told the paper about leading a private life with his five ladies. "[Paparazzi members] shoot me every day coming out of the gym... [but a] married guy with kids? It's not that exciting."

His Martian costar Jessica Chastain also spoke about Damon's affinity for keeping his family under-the-radar. "He's very happy having a private life, which I really respect," the actress noted.

While Damon remains mostly mum about his children, the actor discussed marriage in great detail this past summer after he was asked about his best friend Ben Affleck's split from Jen Garner.

"I think marriage is insane," the Good Will Hunting star noted to Entertainment Tonight. "It's a crazy idea but I love being married to my wife. So I wouldn't tell anybody else about their relationship. But I'm lucky I found my wife. And I guess maybe, if there's any secret … it's to feel lucky."

According to Damon, love and marriage cannot be controlled. "So much of it is out of your hands," he shared. "I mean, I just had that conversation with my father this weekend. He says the same thing to me. Says it's God's grace, is what he said. Because you just don't get lucky."

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