'Jersey Shore' Stars Ronnie and Sammi Back Under Same Roof for Show

"Jersey Shore" stars Ronnie and Sammi were in one of reality TV's most toxic relationships, one that forced her away from the cast for years ... and now the two are shockingly back under the same roof.

We got pics of Ronnie at Margaritaville Resort in Orlando Friday -- the same hotel Sammi, Snooki, The Situation, JWoww, Pauly D, Vinny and Deena are all shacked up to shoot the new season of "Jersey Shore: Family Vacation."

Ronnie's presence is surprising for a multitude of reasons, including the fact Ronnie hasn't been a full-time cast member for several years after stepping away from the show following a string of arrests and domestic violence issues with his ex-girlfriend and mother of his child, Jenn Harley.

Of course, it's also surprising to see him reuniting with everyone while Sammi is around, as she's chosen to steer clear of him for years. Sammi was the only OG cast member who did not return for 'Family Vacation' in 2018 and many speculated she only returned now because Ronnie was no longer in the picture.

It's still unclear if Ronnie and Sammi will shoot any scenes face-to-face or if they'll do parts separately with the other cast, but we do know Sammi's boyfriend is also on the trip ... so it's absolutely not a rekindling type of thing.

Ronnie and Sammi dated off and on through the first 6 seasons of "Jersey Shore" and their fights were explosive -- with furniture thrown from balconies, and one instance where Sammi punched Ronnie in the face.