Chet seemed to be one of many watching Wednesday night's episode of TOWIE, where Megan was accused of sleeping with Chloe Lewis' boyfriend Jake Hall in a fiery confrontation.
Megan - who is currently dating TOWIE's Pete Wicks - strenuously denied these claims and ended up in tears as she told Chloe that she didn't sleep with Jake but she didn't care if she believed her or not.
However, Chet - who starred on the fourth series of EOTB with Megan and her boyfriend at the time Jordan Davies - aired his opinion on the episode.
Taking a swipe at Megan (but not directly naming her), Chet seemed to imply that he thought his former co-star wasn't being honest, and claimed she would "do anything to get to the top".
He tweeted: "She would NEVER admit it [crying with laughter emojis] why is she trying it loooool. U only get so defensive when ur guilty #Fact [sic]."
Once the episode aired, Chet then referenced Megan's engagement to Jordan on EOTB, her brief romance with Geordie Shore star Scotty T on Celebrity Big Brother, and her new romance with Pete.
Chet tweeted: "People will do anything to get [to] the top even getting engaged then getting with the winner of BB now dating a Geeza from towie. #Guilty [sic]."
Protesting her innocence, Megan said she was hoping the rumour wouldn't affect what she has with Pete.
People will do anything to get the top even gettin engaged then getting with the winner of BB now dating a Geeza from towie. #Guilty— Chet Johnson (@Chet_Sket) 6 April 2016
She told the girls during last night's show: "The fact I have this thing going with Pete, this is the last thing I need. I've spoken to him and obviously he has my back 100 per cent. He's not the sort of person to hear a rumour and turn his back on me."
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