Amanda Seyfried highlights her sisterhood bond with Sydney Sweeney

The Housemaid gives a heartfelt bond for Amanda Seyfried and Sydney Sweeney.

The new twisted thriller movie, based on the best-selling novel, stars Sweeney as Millie, a newly hired live-in maid who soon discovers that the lives of her wealthy employers, Nina (Seyfried) and Andrew Winchester (Brandon Sklenar), are far less perfect than they appear.

Speaking with PEOPLE, the co-stars opened up about their connection and feeling supported while being on the set of The Housemaid.

"We related over people’s experiences," Seyfried said, adding that she came to "care about" her scene partner during filming.

"It's easy to support you,” the Mean Girls alum said. “I also probably give way too much unsolicited advice, 'This is what I would do.’”

"No, but I appreciate it," Sweeney chipped in.

Seyfried joked that she knew Sweeney would appreciate it, but she also thought, “Take it with a grain of salt!”

Sweeney, the Euphoria star, then pulls out her phone and slides off the case, revealing a Polaroid of the two of them tucked inside.

“This is how much you changed my life this year, and I love you,” she told Seyfried. “It’s from set. I put it in my phone and never took it out.”

Seyfried beams at the gesture. “Oh, I love that. That makes me so happy,” she said, before adding, “That’s so sweet. I need to get you a four-leaf clover to put back there, my farm is full of them.”

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