Scarlett Johansson may have been honored with a lifetime achievement award, but the star says at home she's "just mom."

While walking the red carpet at the 35th Annual American Cinematheque Awards Thursday, the 36-year-old actress caught up with PEOPLE about life at home as a mom of two. Johansson is mom to daughter Rose Dorothy, 7, and baby boy Cosmo, whom she welcomed in August with husband Colin Jost.

The actress, who took home the coveted American Cinematheque Award, says her family "thankfully" does not think of her as a bigger deal for winning the honor.

"Thankfully [to] everybody just at home, I'm just mom," Johansson told PEOPLE.

Still, the Jojo Rabbit star says there is one exception: "...sometimes [I'm] the Black Widow when it's convenient for my daughter, when she's going to get something out of it."

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