Matthew Rhys Shares How Fatherhood Has Changed Him: ‘I Cry a Lot Easier These Days’ (Exclusive)

Matthew Rhys has fatherhood to thank for helping him prepare for his new film, Hallow Road. 

The Brothers & Sisters star, 50, shared on the red carpet for Hallow Road at SXSW that raising his 8-year-old son, Sam, with partner Keri Russell, 48, helped him slip into the character in the film, in which he plays a concerned father who races against time to help his daughter.

“I think once you do become a parent and you do allow yourself those thoughts ... the thought of having a child go through what happens in the film is horrifying so all you have to do is allow yourself the real thought of it,” Rhys tells PEOPLE. 

“I cry a lot easier these days since I became a father for reasons I don't know why,” he adds.

Hallow Road is a thriller that follows two parents, who “receive a distressing late-night phone call from their daughter after she caused a tragic car accident,” according to a synopsis of the film. Rosamund Pike also stars in the film directed by Babak Anvari. 

Rhys, who also shares two step-children with Russell — River, 17 and Willa Lou, 12 — also noted that there was an additional similarity between himself and his character in that they both had children who could drive.

“[River] has passed his [driving] test in New York, God Bless him,” he joked. “I think if he can drive there he can drive anywhere.” 

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The actor previously opened up about balancing work with parenting their son, in an interview with PEOPLE in June 2024. He shared at the time that they make sure there's always "a parent in the house" to help take care of him.

"What we try to do is – how many of our friends do it – one works when the other one doesn't," Rhys said of their family dynamic. He admitted, though, that "there are moments where you're ships passing in the night to a degree, and that makes it a little tricky."

"But we try not to disrupt home life too much. So that's how we've generally done it. And for the most part, up until now, it seems to work," he explained, joking that he'll now "knock on wood."

Despite how the "logistical element of childcare becomes tricky" if Rhys and Russell work together, he said they're still very much interested in another professional pairing. The couple notably began their romance while starring together on The Americans.

"We definitely would work together [again], we've said that before," Rhys said. "We've just waited. We always said The Americans was so special, it would have to be something akin that we're both so excited to do. It shouldn't just be anything."