Former Big Brother cheater Tully Smyth explains why Lawson is cheating.

Lawson and Cat’s affair on Big Brother has been escalating for weeks. Now Big Brother‘s original cheater, Tully Smyth, has defended the pair’s actions.

Tully Smyth has spoken out on social media about Big Brother‘s cheating scandal involving Cat and Lawson.

If you watched last year’s season, Tully became infamous for her actions in the Big Brother house when she cheated on her girlfriend, Talia, with housemate Drew.

And history has repeated itself with Cat and Lawson this year.

After flirting, massages, stolen kisses and a night in a bathtub, 23-year-old Lawson Reeves and Cat Law, 31, were entangled in a passionate embrace earlier this week before the pair said they loved each other. Lawson's girlfriend of five years, Candice Leeder, has been slowly watching the relationship unfold from the outside.

Tully revealed her thoughts in a series of tweets last night.

"In the wake of last night's @BBAU9 episode, I will say this and this only: there is no point in me making a comment, because it's impossible to make the general public understand the alien mentality of the Big Brother house. Nor could I, or would I, condone cheating no matter what the situation. I feel for Candice and I feel for what Lawson and Cat are going to face once they get back to reality. I would never refer to Drew as a 'mistake' but more an 'ill-timed choice'... that being said, it was a hard life lesson to learn. At the end of the day, I'm human, Lawson and Cat are human and we make mistakes. That's all I'll say on the matter."

iVillage Australia reported yesterday that Candice is set to enter the Big Brother house as an intruder to confront her cheating boyfriend. While this hasn't been confirmed by a rep from Channel 9, Big Brother himself spoke to Daily Mail Australia and refused to deny the rumours.

When asked whether Candice would enter the house, Big Brother said, "Big Brother will get back to you."

Big Brother also revealed he has been talking to Lawson's girlfriend in order to make sure she is okay.

"Big Brother always ensures the welfare of anyone being discussed in the Big Brother house," he said.

Meanwhile inside the house, Lawson has been shown on camera multiple times now apologising to Candice, who has not yet broken it off with the apprentice electrician.

On Tuesday night's episode, Lawson took to the diary room to deliver a message to his girlfriend.

"I would say that I’m sorry for hurting her. I can’t even imagine how she would feel, embarrassed I would assume. She’s a really good person," he said.

"We’ve been through a lot of difficult things, like my mum dying. So I owe her a lot and haven’t really shown that, especially not in here. Her family really looked after me when my mum died. Her mum made me feel like I still had a mum, now I don't think I could look any of them in the eyes."

Have you been watching Big Brother this season? What do you think of Lawson and Cat's cheating scandal? 

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