90 Day Fiancé 's Patrick Resists 'Complicated' Pre-Marriage Demand Thaís Wants Resolved 'Immediately'

90 Day Fiancé's Thaís and Patrick are still not seeing eye to eye.

In an exclusive sneak peek at Sunday's episode, the engaged couple goes out to dinner but tensions quickly rise. "This is the last chance to put the cards on the table and resolve our issues," the Brazilian native, 25, says in a confessional.

"I've already told Patrick a million times that I want to have a voice, but he never listens," she continues. "He always says he's going to get better, that he'll change, and I've only been waiting for this change in him that hasn't happened so far."

At the dinner table, Thaís tells Patrick, 32: "As a couple, we need to decide things together."

"Yes, of course," he replies — and then Thaís revisits a sore subject about which she has very strong feelings.

"If you understand it or not, I want to make one thing very clear: If we get married, I want your brother to leave the house immediately," she demands. "That's all."

TLC

RELATED: 90 Day Fiancé: Thaís's Dad Offers a Stern 'Already?' When She Says She's Marrying Patrick in a Month

Patrick then replies, "John's not going to move out the first month of our marriage."

He continues, "I'll talk to him but it's normal to give a person three months [to move out]."

"You see?" she asks. "I told you to tell John to leave and you said no."

She adds, "I always ask you things and you always say no, but when it's something you want, we just do it."

He replies, "This is way more complicated. You want me to throw my brother to the street, that's not easy. I can't just say 'Hey, John, get out of here.' It's really hard."

TLC

After dinner, Patrick shares his feelings in an interview without Thaís present.

"John moving out is not a simple thing, we lived together for over two years and he's like an integral part of my life."

He acknowledges, "I understand wanting to live alone, but she needs to understand it's gonna take time. It's not something like we just got married and he's out the door right away."

RELATED: 90 Day Fiancé's Thaís and Patrick Butt Heads over New Home: 'This Isn't Gonna Work'

In an episode last month, Thaís didn't hold back as she toured the new place she'd be sharing with the two brothers.

"I'm not enjoying this house because Patrick already did the plans without consulting with me," Thaís explained. "I don't like the fact that John is occupying the entire second floor, so we're left with the small part downstairs."

She added, "I'm not feeling at home, you know?"

After a tour around the new home, John asked what she thought, and she replied, "A little small."

Later in a confessional interview with the brothers, Patrick said, "I'm hoping when everything is moved out and maybe the boxes are gone and we figure out where the furniture goes, she sees that it's a lot bigger."

John added, "I hope that's not a character thing, like she's expecting a mansion from you."

"I don't know," Patrick responded, "I think it's code for like, 'Why does John gotta live here?'"

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Patrick first met Thaís while the former professional weightlifter was reconnecting with his father's family in Brazil. He claimed that he was searching for a Portuguese teacher when he matched with the 25-year-old on a dating app. After a few trips, Patrick eventually won her over with lavish gifts and decided to propose.

90 Day Fiancé airs Sundays at 8 p.m. ET on TLC.