Usually, if someone said artists were collaborating because of similar haristyles we'd tell them their shoulder must now be out of joint because that is a far reach.
But there is (some) evidence that a group of Billie stans are using to push the theory, which is actually pretty convincing.
Billie's brother - and co-writer - Finneas O'Connell recently revealed he was writing a new song for Demi.
We joke not.
"The one that I haven't done yet that I'm most excited about is Lil Nas X, that's just so unbelievably exciting," Finneas told Coup de Main magazine earlier this month. "I also have some writing with Demi Lovato coming up in September, so that'll be cool."
Hold up: Septemeber is now people.
A DemixBillie collab seems off brand for both singers but we are 100% behind it and so is Twitter.
We're already tipping their future single for a 2020 Grammy nom.