Rooney Mara Pregnant, Expecting Second Child With Joaquin Phoenix

The 'Carol' star revealed the happy news Friday, when she stepped onto the carpet at 74th Berlinale International Film Festival and cradled her growing baby bump while posing for pics.

Rooney Mara and Joaquin Phoenix are expanding their family!

Mara revealed the news Friday when she arrived at the 74th Berlinale International Film Festival to promote her new film, La Cocina.

Mara, who wore a strapless, floor-length gown, cradled her growing baby bump while posing for pictures on the carpet.

The Carol actress, 38, and Phoenix, 49, are already parents to son River. The couple named their firstborn after the Joker star's late brother, River Phoenix, who died of a drug overdose in 1993.

The meaningful name chosen for their first child was revealed by Russian filmmaker Victor Kossakovsky, who -- while premiering a film at the Zurich Film Festival in September 2020 -- announced the name to the audience.

"He just got a baby, by the way," Kossakovsky said at the time, "a beautiful son called River."

The otherwise private couple, who first met in 2012 on the set of the sci-fi drama Her, have kept their personal life mostly under wraps and out of the spotlight.

They started dating in 2016, while working on Mary Magdalene together, and later made their red carpet debut at the 70th annual Cannes Film Festival in May 2017, where they were seen holding hands.

Then in 2019, the couple quietly got engaged.

Speaking about their relationship in an interview with Vanity Fair, Phoenix said he thought Mara despised him while they were working together, but learned later that really, she was just shy. They quickly became friends and the rest is history.

"She's the only girl I ever looked up on the internet," he said. "We were just friends, email friends. I'd never done that. Never looked up a girl online."

As for Mara, while she's largely kept mum on their relationship, she has spoken about life as a mother and raising her son with Phoenix.

Appearing on the LaunchLeft podcast, Mara detailed their "creative household" and how the pair have found balance as parents in a two-actor home.

"It feels like a creative household, we're constantly talking about creative things," she said. "It doesn't feel like a two-actor house because I didn't work for the first three and a half years we were together. Basically, since we've been together, I only worked one or two times and one was really small and short."

TooFab has reached out to Mara and Phoenix's reps for comment.