The former glamour model forgave Kieran last year after it emerged he'd been sleeping with best friend Jane Pountney behind her back – but she's made it clear he only has one chance.
Speaking to The Sun on Sunday, a determined Katie said: "If he f**ks up again, I will never, ever take him back. But hopefully things will be OK now he hasn't got a s**t to distract him.
"I've got the Kieran back who I fell in love with, my Prince Charming, not the demon he turned into when he was with Jane. Everything in our relationship has got better."
Katie and Kieran married in January 2013 after a whirlwind romance and welcomed their son Jett that summer. Last year, their daughter Bunny was born. It was while pregnant with Bunny that Katie discovered Kieran had been unfaithful.
She initially vowed to kick part-time stripper Kieran out but then did a U-Turn, saying she wanted to give their relationship another chance.
"Everything is good and we're looking forward to redoing our wedding vows this year," said Katie.
"Last year was s**t but if someone deserves a chance I give them a chance. And I'm glad I did because I would have lost a family unit."
Katie has left Kieran in charge of the kids – including Harvey - while she's in the Big Brother house, while ex-husband Peter Andre will be looking after Princess and Junior.
Ahead of entering the house, she said of Kieran being head of the house: "Well he handles it anyway, because if I go to work he has the kids. He's really good with the kids and we're a good team.
"He will miss me and I'll miss him and the kids. That is my biggest thing, the family. It's going to be hard because I don't even like having a night away from them, but I know that is part of the deal and you just have to get on with it."
CBB stars without make-up in pictures:
Copyright: Channel 5
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