Scarlett Johansson, Colin Jost Welcome Son, Reveal Newborn's Name Days After Confirming Pregnancy

Scarlett Johansson and Colin Jost have welcomed their first baby together.

The "Black Widow" actress' rep Marcel Pariseau confirmed the happy news to People Wednesday. Johansson is also mom to daughter Rose Dorothy, 6, whom she shares with her ex-husband, Romain Dauriac.

The news comes just days after Johansson's "Saturday Night Live" star husband confirmed her pregnancy during a stand-up performance at The Ridgefield Playhouse in Connecticut Sunday, a source told People.

"We're having a baby. It's exciting," he said during his set, according to Us Weekly.

Later Wednesday, Colin took to Instagram to reveal the name and sex of their child. "OK OK we had a baby. His name is Cosmo. We love him very much," the 39-year-old actor wrote. "Privacy would be greatly appreciated."

Jost went on to joke, "For all inquiries, please contact our publicist [Michael Che]."

The comedian then added several hashtags, including, "#wegotawaywithitforalongtime #nokidspolicy #we’regoingtodisneyworld."

Fans sent the couple congratulatory messages for the arrival of their bundle of joy.

"Appreciation tweet for Scarlett Johansson and Colin Jost who deserve only happiness in their lives. Their baby is just the luckiest baby in the entire world," one fan tweeted.

The memes also started rolling in after Jost announced the name of their child.

"Scarlett Johansson and Colin Jost named their son Cosmo so they’d have an excuse to name their next kid Wanda," one Twitter user wrote, adding a photo of Elizabeth Olsen's character Wanda Maximoff, a.k.a. Scarlet Witch.

Johansson sparked pregnancy rumors last month after reportedly skipping several promotional events for her film, "Black Widow."

"She hasn’t been doing many interviews or events to promote ‘Black Widow,’ which is surprising since it is a huge Marvel/Disney release and she is both the star and an executive producer," an unnamed source told Page Six.

The outlet also noted that she only shot herself from shoulders and up when she carried out promotional appearances via Zoom. This was the case when she made a virtual appearance on "The Tonight Show" on June 21.

"Scarlett usually spends a lot of the summer out in Amagansett and Montauk, and you’d often see her walking her dogs on the beach or getting coffee. But this summer it seems like she is deliberately trying to keep a low profile," an unnamed Hamptons source told Page Six last month.

Johansson and Jost got engaged in May 2019 after two years of dating. The "Sing 2" actress debuted her 11-carat engagement ring that July at the San Diego Comic-Con. They wed in an intimate ceremony back in October 2020.