Jost confirmed the baby news on Instagram, stating that they love their newest family member "very much".
Scarlett and Colin first met in 2017, became engaged in 2019 and got married this past October.
Reports that Johansson was expecting started circulating in July when the superstar didn't turn up for the red carpet premiere of her latest film Black Widow.
The newborn is the first for Johansson and Jost; however, the actor already has a daughter Rose Dorothy Dauriac who she shares with her ex-husband, Romain Dauriac.
Watch the video above for more.
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