The gals, along with several other friends, celebrated in New York City with a day that included a bike ride in sneakers, jeans and a long green coat with furry trim, watching horse shows on TV, karaoke, balloons, flowers and even a homemade cake baked by Hadid.
The Keeping Up With the Kardashians star also received plenty of love from her family on her big day: Sisters Kourtney, Kim and Khloé Kardashian and Kylie Jenner all posted Instagram tributes to their sibling.
Kourtney, 39, kept it simple, posting several video clips and photos with the supermodel on Instagram Stories on Saturday, as did Kim, 38, who captioned a photo of Kendall smiling, “Love you Kenny.”
Khloé, 34, and Kylie, 21, meanwhile, shared photo galleries through the years with their sister, who was spotted hanging out with ex-boyfriend Ben Simmons on Thursday, November 1.
“Happy birthday my sweet Kenny! I love you for who you are and couldn’t imagine a life without YOU,” the Good American designer wrote. “If anyone knows you like I do, they know how much of an amazing, kind, quirky, loving person you are and how much any one would dream to have you in their life. Some people aren’t as lucky as us – not everyone gets to have a sister and not everyone gets to have a love and bond that all us siblings have with one another. Blessed we are! We all celebrate you today and everyday! Let your confidence continue to shine and never be anyone but yourself. You are perfect in every single way. I love you my sweet angel sister!”
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