Kim, 38, and Kourtney, 39, blew kissy lips for the camera in the back of their car as they made their way to Paris' event.
Paris, 38, looked glittery and glamorous in a sparkly grey jumpsuit with a ton of cleavage exposed.
The mother-of-three opted to wear something a bit simpler compared to the party host.
The party's theme was for St. Patrick's Day but also revolved around Paris' 38th birthday, which took place on February 17. "Even though your birthday was months ago, this is how she celebrates it," Kim said.
Kourtney appeared to be having a blast as well as she tried on a pair of stunner shades while relaxing in her stunning all-black ensemble.
Kim and Paris, who have had an up and down relationship for years, looked blissfully happy to be with each other during the fun evening.
Other attendees at Paris' event included The Hills: New Beginnings star Frankie Delgado and KarJenner family friend Larsa Pippen, who just filed for divorce from her husband Scottie.
Who was best dressed at Paris' shindig? Sound off in the comments!