Kylie Jenner's 18th Birthday: Sister Kourtney Kardashian Slays in Sexy Outfit During Bash

Kylie Jenner is finally 18 years old, and this year her birthday celebrations were probably one of the most trending topics of the weekend! Jenner's alleged boyfriend, Tyga got her a Ferrari, but that news wasn't the only topic of discussion Sunday night. MStars News has learned that Scott Disick's ex and baby mama, Kourtney Kardashian was spotted looking quite sexy during her baby sister's birthday party.

According to Hollywood Life, the two venues where Kylie celebrated her 18th birthday were Bootsy Bellows and The Nice Guy where all of her sisters including Kim, Kourtney, Khloe, and Kendall attended.

 #KylieJennerTurns18 #KimKardashian #KourtneyKardashian #KendallJenner #KhloeKardashian - Khloe was there with her boo #JamesHarden

A photo posted by The Shade Room (@theshaderoominc) on Aug 10, 2015 at 3:04am PDT

Kourtney gave everyone a run for their money when she showed up looking fabulous in her cut-out jumpsuit.

KOURTNEY WAS ABSOLUTLY GORGEOUS ♡ #kourtneykardashian @kourtneykardash A photo posted by kardashians jenners & wests (@kuwtk.dash) on Aug 10, 2015 at 9:17am PDT

The mother-of-three had us here at MStars News wanting to go hit the gym! If she was trying to make her ex, Scott jealous, we're sure her outfit did catch some kind of attention from him.

Besides getting "turnt up" with her sisters, Kylie's friends and parents, Caitlyn and Kris Jenner were also in the room to wish their daughter a Happy Birthday.

 MY GIRLS. party night. #18@12

A photo posted by King Kylie (@kyliejenner) on Aug 9, 2015 at 10:35pm PDT

The former couple even reunited over the weekend to celebrate Kylie's birthday at home.

Thankfully, there were no crazy rumors of drugs at Kylie Jenner's birthday bash. MStars News previosly reported that some followers of the Kardashians spoiled their last family party, which was Kylie and Kendall's graduation celebration, claiming that people were doing cocaine at the party.

The parent trap A photo posted by Kim Kardashian West (@kimkardashian) on Aug 7, 2015 at 10:45pm PDT

Also in attendance over the weekend at Kylie's birthday was Kim's husband, Kanye West, Kris' man, Corey Gamble, and Khloe's alleged new beau, James Harden.  Camera's caught Khloe and James leaving together.

Koko and James yesterday ♡ // they look so good together #khloekardashian #jamesharden A photo posted by kardashians jenners & wests (@kuwtk.dash) on Aug 10, 2015 at 9:15am PDT

MStars News is still in shock after Tyga gifted Kylie an expensive car as a birthday gift! She seemed shocked, too, from the looks of the video below.

#TSR is in the building at #KylieJenner 's 18th #Bday party & #Tyga bought her a #Rari A video posted by The Shade Room (@theshaderoominc) on Aug 10, 2015 at 1:17am PDT

If that isn't a relationship confirmation, we don't know what else you possibly need! MStars News wants to hear from our readers out there. Do you believe that was too much for an 18-year-old to recieve on her birthday? Do you think Kylie's parents, Caitlyn and Kris approved of the car, gifted by Tyga? Sound off below!

Im in love with their love Kyga ♡ she looks so happy #kyliejenner #tyga #kyga A photo posted by kardashians jenners & wests (@kuwtk.dash) on Aug 10, 2015 at 9:21am PDT