Summer's almost over, but not before the hottest girl squad shows off their bathing suit bodies!

Hailey Baldwin, Gigi Hadid, and Kylie Jenner just took to Instagram to flaunt their bikini bods, and we can't decide who is the sexiest! While it's pretty obvious Kyls just wants to show off her huge enhanced ass and Gigi wants to flaunt being on vacation with boyfriend Zayn Malik, Hailey seems to posting for a more subtle reason.

The blonde Guess model is reportedly "super upset" that Justin Bieber has unfollowed her now that he's moved on with Sofia Richie, so perhaps she's trying to show him what he's missing? Not to be mean, but she's way more smokin' than Lionel Richie's daughter!

"Hailey is very upset about Justin. She's sad about him because he's been flaunting around Sofia. She thinks some of the Instagrams he's posted lately with Sofia are pointed and really about Hailey, so it's no surprise she took to Instagram herself to express that," a source dished to E! News.

No wonder they have so many followers!