What happened between Paul and Awhina's twin sister Cleo? Their history explained

It's a small world and it gets even smaller when you step into the Married At First Sight bubble, or so groom Paul quickly learned.

In Monday night's episode, viewers learned that Paul, who is married to Carina, and Awhina, who is married to Adrian, shared a personal history of sorts.

A few years prior to the experiment, Awhina's twin sister Cleo and Paul slept together and dated.

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"They're both from Perth and they were very casual, it was a couple of years ago, very short-lived," Awhina told cameras.

"[Cleo] had nothing bad to say about Paul."

Paul had already told Carina about his history with Awhina's twin sister Cleo but their past relationship came to light again as the participants learned they would be swapping partners as part of a Feedback Week task.

EXCLUSIVE: Watch Evelyn and Duncan's fiery reactions as Jamie erupts at Carina and Rhi in Dinner Party showdown

Awhina would be moving in with Paul and while at first she thought it could be "weird" she quickly came around to the idea.

Paul's wife Carina on the other hand was devastated by the idea of a woman, let alone the twin sister of a woman he'd slept with, moving in with her husband.

"No hard feelings towards Awhina but Awhina and her sister look identical so I don't want Awhina moving into our apartment and sleeping in our bed with my husband," Carina vented to cameras.

After a few tears and some time alone, Carina eventually moved out and agreed to take part in the partner swapping task and so Awhina moved in with Paul.

The task turned out to be exactly the opportunity Paul needed to get a few things off his chest.

WATCH: MAFS bride Carina reveals co-star she no longer speaks to after 'volatile, nasty' behaviour

He and Awhina had already established a solid friendship throughout the experiment and so Paul opened up about some doubts he had about wife Carina in a letter.

"I feel like [Carina] is a little bit of a snob sometimes and come across as very judgey, and I'll be honest with you this is giving me the ick," Paul read out to Awhina.

Paul continued to explain to Awhina that when he told Carina about his past with Cleo, she made the comment: "I didn't know you would go for that kind of calibre".

You can hear all of Paul's letter in the video below:

Awhina was obviously outraged by Carina's comment.

"Where are you in your life, Carina, to look down at my twin sister," Awhina raged to cameras.

This only marked the start of what we're sure will erupt into a feud between Awhina and Carina.

Married At First Sight airs Sunday at 7pm and Monday to Wednesday at 7:30pm on Channel 9 and 9Now.

Want more exclusives? Season 10 stars Evelyn and Duncan recap this week's explosive Dinner Party.

Stream every episode of Married At First Sight for free on 9Now

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