By Hanna Flanagan
November 06, 2019 09:00 AM

It’ll be a glamorous New Year’s Eve wedding for Erin Foster!

And in true Foster sister fashion, the Bumble entrepreneurs are getting painfully honest about planning Erin’s upcoming nuptials.

“[Erin] sounds like Bridezilla,” Sara — who was the first to reveal her sister’s engagement to businessman Simon Tikhman on Instagram back in August — jokingly tells PEOPLE ahead of the sister’s La Mer campaign launch. “Everything has stopped. Everything has halted. Our lives have stopped for this f—— wedding.”

Erin and Tilkman, who started dating in August 2018, didn’t want to spend a year planning their wedding — the couple just wanted to start their lives together as soon as possible.

And while Erin never saw herself as the “Bridezilla” type, she admits she’s definitely feeling the pressure of a short engagement.

“I think the timeframe is the most challenging thing. Having a wedding date during the holidays is really complicated,” she says. Joking that “people with kids are like ‘you should be ashamed of yourself for what you did to us.'”

La Mer

RELATED: Erin Foster Documents the Elaborate Faux Wedding Her Fiancé Planned for Surprise Proposal

“You only get one chance and you just want it, it’s mostly the thing that haunts you,” Erin adds. “You want it to be great for everybody else. You want everyone to have an amazing experience.”

Sara Foster/Instagram

To which Sara responds: “At least you’re going into it with the mentality of it only happens once. I feel like people in [Los Angeles] are like ‘Oh, it’s fine. It’s the second.'”

But Erin is making her life a bit easier by bucking tradition for the New Year’s Eve ceremony: “I’m not doing a bridal party,” the Barely Famous star tells PEOPLE. “It’s too complicated.”

Debra Morrison

The second non-traditional (and dare we say taboo) element of the ceremony will be Sara’s white Monique Lhuillier dress, which Erin called a “wedding dress” but totally approves of.

But don’t worry, Sara assures she won’t upstage the bride by accessorizing with a train or a veil. “I’m not that big of a monster,” she says.

RELATED: Sara and Erin Foster Get Real About Skin Care and Aging in Los Angeles

In September, Erin opened up to PEOPLE about diving into the wedding planning process.

“We just want to be married, and we’re just excited about that,” she said. “We started right away to get the ball rolling.”

MOVI inc.

“I really do see the way that it stresses people out,” Erin continued. “And I’m really guilty of being someone who gets stressed really easily and gets anxiety about so many things — anxiety this person doesn’t like the location, this person doesn’t like the date, this person disagrees with how you’re going to do it.”

As to what she’s most looking forward to about her wedding day?

“It being over, probably,” she joked at the time. “All I really want is a wedding where people aren’t on their phones and they’re happy for us.”

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