North modeled some of her auntie Kylie's lip kits.
Photo: Instagram/@kylizzlesnapchats
2/5
North and her friend Ryan had some fun with Kylie's lip kits.
Photo: Instagram/@kylizzlesnapchats
3/5
Kylie's sisters Kendall and Kourtney were in attendance for the birthday party as well as parents, Caitlyn and Kris Jenner.
Photo: Instagram/@kylizzlesnapchats
4/5
Kylie and her boyfriend Tyga celebrated his son's fourth birthday with a Ferrari-themed birthday party.
Photo: Instagram/@kylizzlesnapchats
5/5
Rob Kardashian took to his Instagram to wish his future stepson a happy fourth birthday.
Photo: Instagram/@robkardashian