The Black Widow star told Entertainment Tonight that she feels "very fortunate" to have been able to take plenty of time away from work to be with her new arrival.
"I've been able to take this time to really enjoy the early stages of my motherhood with our son. It's been wonderful. I'm in a baby bliss bubble".
However, Scarlet says her first child Rose (from a previous relationship) is a typical "busy" and talkative seven-year-old and not too interested in her baby brother at the moment.
"She's kind of like, 'Oh yeah, he's cute'. so, all this happened,'[just] non-stop talk".
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