Fans of the ITV2 show were quite surprised when Chloe and Mario were pictured snogging on a London street during a night out on 18 March.
Probably not as surprised as Charlie, though!
Chatting to the TOWIE official website, Charlie said: "It's mixed emotions, really, because I know Mario really well, obviously, and I know a lot of his history and past, and that's cool, but this is my sister which is a whole different ball game."
Viewers of Sunday night's episode saw Charlie admitting that he honestly didn't know what was going on between Mario and Chloe, but saying he couldn't stop two people liking each other.
He reiterated that stance to the official website, adding that he doesn't know what the future will hold but if Mario and Chloe do like each other then they have his blessing.
"This will either be a really fortunate situation or a really unfortunate situation where it all ends in tears," he said.
Charlie concluded that if there is a spark there, they should go on some dates and see how it works, but if they don't like each other they should forget it all now, move on and just stay friends.
On Sunday night's episode, we saw Chloe chatting to pal Ferne McCann about the kiss, saying: "It just happened. He kissed me – and it was a really good kiss!"
When quizzed if that had been their only kiss, a coy Chloe replied: "One kiss that we got caught for! It's been a secret but I feel like I just want people to know now so it can not be a secret and we can see what happens."
Does that suggest she's interested in seeing where it goes?
Mario, meanwhile, hasn't addressed the kiss. Playing his cards close to his chest, perhaps? We'll certainly be tuning in to the next episode on Wednesday night to see how this all develops!
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