The glamour model – who is six months pregnant - is said to have requested Kieran leave their property and shack up in the log cabin at the bottom of the garden.
According to The Daily Mirror, it's so Katie can figure out what she wants to do following the heartbreaking accusation that Kieran had a sexual affair with her best friend.
"Katie is feeling very vulnerable and is at a real loss. It is all so sad. By having Kieran in the log cabin, it gives her the space to sort her head out and keep tabs on what he is doing," said a source.
Katie shocked fans this week by sending a flurry of tweets branding Kieran "disgusting" after learning he'd allegedly been sleeping with close friend Jane Pountney, a married mother.
The allegations came just three days after Katie revealed she is pregnant with her and Kieran's second child. They are already parents to son Jett, nearly one.
In a statement she later issued: ""I appreciate most people will have seen my tweets on the subject of my marriage to Kieran.
"I make no apologies for them though it will be appreciated that, sending them immediately after Kieran confirmed to me what he had been doing for the last 7 months, those tweets were a sign of my heart breaking."
She added: "That he was doing it with a close friend of nearly 20 years is hard to understand."
Kieran has yet to comment on the allegations, while the alleged other woman has also remained quiet.
Her husband Derrick, however, spoke out yesterday, saying: "A lot of this drama has been a storm in a teacup and there's a lot of misunderstandings to sort out.
"Now Katie has gone and put the whole thing for everyone to read about on Twitter, which she didn't really need to do, and a drunk kiss has turned into a full-on affair."
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