Bella took to Instagram Story to share a photo of a cake she made her bestie, as well as all the decorations they put up in honor of the birthday girl. In one pic, Kendall is wearing a long-sleeve black shirt with jeans, and is holding a balloon animal.
The models, along with Justine Skye and Renell Medrano, were casually dressed and also hopped onto a party bus at some point during the night.
Earlier in the day Jenner was all smiles as she was spotted cruising around the city in a Citi Bike, donning an eye-catching bright green furry coat by Saks Potts.
Kendall recently reflected on how far she's come in an interview with Daniel Chetrit of ZAZA WORLD RADIO, and expressed how thankful she is for those closest to her.
Crediting her friends and family for helping her navigate the more difficult side of fame, she said: "I think that if I didn't have you guys, my homies, and my family around me, the people that I love so much, I would not have the same security within myself to be able to look at those comments and not care about them."