Rob posted the video Saturday with caption, "Had to post this snap my sis sent me. LOL she's got jokes! #KimsCryFace." It's clear Kim's kidding around ... but it's the first time we've seen any of the sisters come close to addressing Rob's engagement.
It's unclear just how often the siblings have gone back and forth ... but if Kim's making light of the situation, you gotta think the others will follow.