Colin Jost Details Relationship Between Son Cosmo and Scarlett Johansson’s Daughter Rose

Colin Jost gave an inside look into how his and Scarlett Johansson’s 3-year-old son Cosmo gets along with her and ex-husband Romain Duriac’s 10-year-old daughter Rose.

Live from New York, it’s Colin Jost with an adorable update.

The Saturday Night Live star gave an inside look into his life at home with wife Scarlett Johansson, their 3-year-old son Cosmo and the actress’ 10-year-old daughter Rose (who she shares with ex Romain Duriac).

“The two of them spent a lot of time together this summer, which was nice for them,” the comedian exclusively told E! News. “She’s a very nice, loving sister.”

Because assembling their brood isn’t always easy.  “Normally she’s got her own life,” Jost—whose new comedy special Colin Jost & Michael Che Present: New York After Dark airs on Peacock Sept. 12 at 9 p.m. ET—continued, “but this time she was forced to stay with him for a lot of time, and they got along really well.”

Which means Rose was also there for one of Cosmo’s biggest milestones yet.

“He drank some milk and then said, ‘Some things in life you just have to savor,’” the 42-year-old star recounted of his son’s deadpan joke. “Which I thought was nice.” (For more with Colin and Michael, tune into E! News tonight, Sept. 11.)

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After which Colin confirmed, “He is funny. He’s sort of shy sometimes, but he’s a gregarious little guy. He’s fun.”

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Colin’s glimpse into his and Scarlett’s private life comes as a rare occurrence, as the two often opt to maintain a low profile since tying the knot in 2020.

Scarlett has, however, previously revealed how Rose first adjusted to her big sister duties after welcoming Cosmo in 2021.

“She’s pretty neutral about it,” the Black Widow star said during an appearance on The Ellen DeGeneres Show in 2021, “which I think is a good thing.”

She continued, “I imagine that they’ll be very different people. You know, my daughter is a little bossy. I don’t know where she gets it from, and she’s very headstrong…Well, he’s just putting his feet in his mouth. So, he seems pretty laid-back.”

Her motherhood journey hasn’t been so chill, rightfully so.

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“It’s really tough,” Scarlett said during an April 2023 appearance on The Skinny Confidential Him & Her Podcast. “I remember my daughter when she was 2, I said, ‘This is great. I don’t know what everybody is talking about.’ And then she turned 3, and it’s like being in an emotionally abusive relationship.”

“It’s crazy, very intense emotional swings and so bossy and adamant,” she recalled of that toddler era. “And also these huge, constant mood swings…You’re up and down constantly.”

Babies, on the other hand, are much easier to handle.

“Having a baby is so lovely,” she gushed. “They’re so cute. They sit there and they love you and then that’s it. And you just get love from them.”