Joaquin Phoenix and Rooney Mara have reportedly welcomed their first child together.

Director Viktor Kossakovsky claimed that the actors have become first-time parents while speaking during a Q&A session at this weekend’s 2020 Zurich Film Festival.

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Kossakovsky alleged that the couple welcomed a son named River last month.

The name is thought to be a tribute to Phoenix’s late brother, River, who tragically passed away due to a drug overdose in 1993.

The Q&A session took place after a screening of “Gunda”, which Phoenix worked on as an executive producer.

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The notoriously private couple — who met while filming 2013’s “Her” — have been linked since 2016, when they reunited for “Mary Magdalene”, in which Mara played the title role while Phoenix played Jesus. They reportedly got engaged last May, though they have never commented on it.

ET has reached out to their reps for comment.

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