Joaquin Phoenix, Rooney Mara reportedly named new baby after late River Phoenix

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

However, the private actors weren’t the ones to reveal the news. It was Russian filmmaker Victor Kossakovsky who spilled the beans this weekend while promoting his film “Gunda” at the Zurich Film Festival.

Reps for Phoenix and Mara did not immediately respond to The Times’ requests for confirmation.

Kossakovsky was asked how he got “Joker” star Phoenix to board his animal-rights documentary (Hint: It had a lot to do with Phoenix’s 2020 Oscars acceptance speech), and then he shared the news.

“He just got a baby, by the way,” Kossakovsky said Sunday while speaking onstage at the festival. “A beautiful son called River.”

River, of course, is the late musician and “Stand by Me” actor who died in 1993 after a drug overdose that included lethal levels of cocaine and morphine. The rising star was 23.

Phoenix has spoken of his elder brother’s tragic death in interviews and paid tribute to him during awards season.

The actor, 45, and Mara, 35, best known for her role in “The Girl With the Dragon Tattoo,” met in 2013 on the set of the film “Her.” They stepped out as a couple at the 2017 Cannes Film Festival and reportedly were engaged last year. The two also costarred in Gus Van Sant’s 2018 comedy “Don’t Worry, He Won’t Get Far on Foot.”

River is the first child for each of them.