Turns out, it was actually Kris Jenner's old swimsuit from the 1980's! The momager posted this side-by-side on her Instagram account with the caption, "Ohhhhhhh so THIS is where my vintage Body Glove bathing suit went! @kyliejenner you are grounded! Wait, I can't do that anymore you're 18."
She also included the hashtags #whoworeitbetter (how can we possibly decide?) and #whoknewyouwouldlikemyoldstuff. True that. It's kind of funny how in fashion, what's old is often new again. We've all been there before where we look through our mom's old stuff that we totally made fun of her for saving and then suddenly we're SO glad she did because it's totally trendy.
Kris' old swimsuit seems to have been a pretty big hit during the vacay. Kylie's friend Anastasia, who was there celebrating with her, shared this pic of herself rocking it and also looking awesome:
Kylie was joined by Tyga, sister Kendall Jenner and a bunch of her other friends on the trip, including singer Pia Mia. The crew stayed at Girls Gone Wild founder Joe Francis' house in Punta Mita and Joe's girlfriend Abbey Wilson shared this pic of the whole crew when the trip was over:
Kylie doesn't have too much time to get comfy back at home, though. She's hosting a birthday bash in Canada on the 16th.