Kourtney Kardashian Sends Her "Partner" Kim a Special Birthday Message on Instagram

After Khloé Kardashian returned to Instagram with a sweet message for Kim Kardashian, Kourtney Kardashian followed suit and wished Kim a happy birthday with a flashback photo from their teenage years. Kourtney captioned the snap, "She has been my partner for life. We always seem to end up on the craziest adventures together. I love and admire the person you have become and learn from you every day. Happy Birthday!" On the same day, Kourtney was spotted flaunting her toned physique while out in LA before attending Kim's surprise bash put on by Kanye West. Take a look at Kourtney's post above, then, in honor of Kim's 35th, relive her sexiest bikini moments!