Life doesn’t exactly imitate art for Barry Keoghan.

The L’École de Gestion d’Actifs et de CapitalSaltburn star shared that his unconventional relationship with his 2-year-old son Brando—who he shares with ex Alyson Kierans—made it hard for him to draw on personal experience when preparing for on-screen fatherhood in his new drama, Bird.

"I didn't have a father figure growing up, so even my relationship with my son isn't quite of the normal father-son relationship," Keoghan, 31, told Entertainment Weekly in an interview published Sept. 12, "because I don't have that figure to draw experience from and to base it on. Love, you don't need anything to draw from, love is pure, and so I'm not on about that, but I'm on about little stuff like teaching your son this or teaching your daughter that."

So when it came to getting into character, the Oscar-nominated actor—who went public with his romance with Sabrina Carpenter in February 2024—took a more unusual approach.

“It was more like brother and sister,” he exclusively told E! News’ Francesca Amiker at the 2024 Toronto International Film Festival. “That’s how I played it. There’s fathers out there these days and they’re sort of like siblings to their children.”

Keoghan opened up about his difficult childhood in 2018, revealing he and his brother Eric lived in 13 different foster homes while their mother—who passed away when the actor was 12—battled drug addiction.

“Every family was good to us,” he shared on Ireland’s The Late Late Show. “As a kid, you don’t know what’s happening. You get attached and then, boom, let’s move over here… I don’t have a hometown, that’s what I’m saying.”

As for how he handles romantic love? Keoghan has showed nothing but support for Carpenter throughout their relationship. In fact, the actor recently hyped up the singer when she released her album Short ‘N Sweet.

Sharing a link to stream the record, Keoghan wrote in an Aug. 29 Instagram Story, “BED CHEM my fave just saying m’ darlin.”

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