Joaquin Phoenix and Rooney Mara have welcomed their first child together, a baby boy named after the actor’s late brother, River Phoenix. 

While the press-averse couple have yet to formally announce the news, director Victor Kossakovsky, who worked with Joaquin Phoenix on the wordless, black-and-white documentary “Gunda,” confirmed the newborn’s arrival on Sunday at the 2020 Zurich Film Festival.

“He just got a baby by the way,” the director said when asked about the actor at a screening of the film. “A beautiful son called River.”

River Phoenix died in 1993 of a drug overdose at age 23 at the height of his fame after starring in films like “Stand By Me” and “My Own Private Idaho.”

He collapsed outside of the popular West Hollywood nightclub The Viper Room on Halloween night while out with the “Joker” star, who was just 19 years old at the time and called the police for help. 

Joaquin Phoenix, of course, has since followed in his brother’s footsteps, making a name for himself in the film industry, while keeping River Phoenix’s memory alive all these years later.

During his 2019 Oscar speech, while accepting the Best Actor trophy for his performance in “Joker,” the actor made special mention of River Phoenix, while Mara watched on in the audience.

“When he was 17, my brother wrote this lyric,” Joaquin Phoenix said at the end of his speech. “He said, ‘Run to the rescue, and love and peace will follow.’ Thank you.”

The actor has been reluctant to speak about his brother in the press given the media attention surrounding his death at the time, but spoke candidly about River Phoenix’s lasting legacy in a “60 Minutes” interview with Anderson Cooper last year. 

“I feel like in virtually every movie that I made, there was a connection to River in some way,” he said. “And I think that we’ve all felt his presence and guidance in our lives in numerous ways.”

Mara and Joaquin Phoenix, who got engaged last year, first met on the set of the 2013 film “Her.”

Joaquin Phoenix initially believed that Mara “despised” him upon their first meeting, but the two later developed a mutual attraction.

“She’s the only girl I ever looked up on the internet,” he told Vanity Fair. “We were just friends, email friends. I’d never done that. Never looked up a girl online.”

They went onto spark a romance after starring in two more films together, “Don’t Worry, He Won’t Get Far on Foot” and “Mary Magdalene,” and made their red carpet debut as a couple at the 2017 Cannes Film Festival. 

Reports circulated in May that the couple were expecting a child together, but neither spoke out at the time about the rumours.