"They're the most charming, clever, adorable little ones," Drew Barrymore's costar Liv Hewson tells PEOPLE of Barrymore's daughters Frankie and Olive
Premiere Of Netflix's "Santa Clarita Diet"
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There’s no denying that Drew Barrymore is a boss in the world of Hollywood, but when it comes to her home life, her daughters keep her in check.

Barrymore — no stranger to childhood on film sets — sometimes brought daughters Frankie, 2½, and Olive, 4, to the set of her new Netflix horror-comedy series Santa Clarita Diet. And though the zombie subject matter is a little bit adult for the young girls, they didn’t hesitate in staking their claim on Mom’s set.

“They’re the cutest munchkins in the world,” Barrymore’s costar Skyler Gisondo told PEOPLE Wednesday at the series’ premiere in Hollywood, California.

“They’re the most charming, clever, adorable little ones,” adds Liv Hewson, who plays Barrymore’s daughter in the series.

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Gisondo shared a funny anecdote of a time when Barrymore brought the girls to set.

“We were having a rehearsal one day, this was towards the end. There’s a very relaxed vibe on set, and she had one kid on each leg,” he says of the show-business veteran.

“And during the middle of the scene, she was saying a line, and one of the daughters was like, ‘Mommy, be quiet.’ ”

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But not even a shushing from her daughter could derail Barrymore’s naturally sweet temperament — even if she was rehearsing.

“She’s like, ‘Sweetie, this is my job. I have to say this stuff, but I can be quiet later, we’ll talk later,’ ” Gisondo adds. “[The daughter] was like, ‘Okay.’ Then for the rest of the scene, she just watched.”

Santa Clarita Diet is available for streaming on Netflix now.