There were three in the bed and the posh one said..
But luckily we no longer need to wonder as her Made In Chelsea co-star Spencer Matthews has decided to fill us all in on all the gory details - including whether Cags really has had a ride in Hazza's Chelsea tractor, if you know what we mean..
Spence might've had a bit of a thing for Caggie in the past but it sounds like their fling is a distant memory that's been overtaken by his desire for a slice of the Harry Styles love sandwich.
"He's great, I'm a massive Harry fan - I was like, 'Lucky bird!'," he explained to Heat.
Apparently the idea of Hazza and Caggie having a snog isn't news to Spencer and apparently he was in on all the dirty details from the start.
"I've known about that for absolutely ages, they hooked up a long time ago. I don't think they've slept together.
"I said, 'What's he like in bed?' and she said, 'I don't know.' I think if she had shagged him she'd have told me. I don't care if they have or not, so why lie about it?"
Well maybe in case you tell the whole world during an interview, hey Spence?
That aside, Louis probably doesn't need to get his sassypants out just yet as despite being a bit of a fan, Spence is yet to meet Harry in person, even if they are already pen pals.
"We were BBM pals until I broke my phone. I no longer have his PIN," Spencer added.
So there we have it - according to the super sleuth that is Spencer Matthews, Caggie and Harry have never shagged.
But is that case closed or does it just open up a whole new can of worms? Comments below please.