America Ferrera Says Her Kids Have No Idea She's Starring in Barbie Film: 'They're Still Too Young'

America Ferrera's two children are blissfully unaware that their famous mother is going to star in one of 2023's most anticipated films.

While chatting with PEOPLE about her partnership with Zumba for its new Zumba Beginnings program, the actress, 38, also opens up about how her two children — son Sebastian Piers, 4, and daughter Lucia Marisol, 2, whom she shares with husband Ryan Piers Williams — have no idea she'll be starring in the upcoming Barbie movie.

"They don't really have any context for it," Ferrera tells PEOPLE exclusively. "So one day [they might care]. But not now, they're still too young."

Barbie, which is due to hit theaters on July 21 stars Margot Robbie as the iconic Mattel doll and Ryan Gosling as Ken, her male counterpart. Other stars featured in the film include Will Ferrell, Issa Rae, Simu Liu, Kate McKinnon and Michael Cera, among others.

Though Ferrera remains mum on who exactly she is portraying in the project — stating that director Greta Gerwig "would be not happy with me" if she disclosed her role — the Sisterhood of the Traveling Pants star says, "People don't have any idea what to expect [with the film], and I think that that's the right vibe. Whatever you think it is, it's not that. It's something else."

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America Ferrera/Instagram

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Back in July, filming on Barbie wrapped and was marked with a behind-the-scenes photo on Instagram that was shared by two actors from the upcoming comedy, Sharon Rooney and Hari Nef.

Featuring Ferrera alongside Robbie, 32, and Gerwig, 39, the image also showed other costars Alexandra Shipp, Emma Mackey and Ana Cruz Kayne.

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"It's a wrap for the Doll! see you in Barbieland," Nef captioned her post, while Rooney wrote alongside the same photo on her page, "Barbie, a true gift."

Another cast member, Ariana Greenblatt, also tweeted her last day of filming for the movie at the time as well. "Left barbie land today. what a special place to be in," wrote Greenblatt. "i love & respect every person on this film and i'm so excited for the world to see what we have created. (really see it;) off to start my new journey! don't forget to wear as much pink as you can in honor of Barbie."

RELATED VIDEO: Eva Mendes Reacts to Ryan Gosling's First Character Photo from Barbie Movie: 'That's My Ken'

With Barbie wrapped, Ferrera tells PEOPLE she now is looking forward to another exciting time in her life — celebrating Halloween with her kids.

Though she admits it is a "bummer" that son Sebastian wants to rewear his space person costume from 2021, Ferrera says she asked him, "'Can we get you a different space suit?' " to which she says he replied, "'I have a space suit, I'm good.' "

America Ferrera/Instagram

"So he is doing his part in not adding to Halloween waste," she adds with a laugh. "And my daughter hasn't yet told me what she wants to be. I keep asking her, but they're 2 and 4, so we're still in the stage where they're learning that holidays are these shared collective moments of excitement that everyone is in on."

"We were kind of there last Christmas, and we're getting closer, but I feel like they need more experiences of, 'Oh, this is what Halloween is,' for them to really get that deeply into it," continues Ferrera. "I think [my husband and I are] still more excited about it than they are, so I'm hoping that changes soon."