Kris shared a collage of pictures featuring herself and Kourtney throughout the years, and gushed about her daughter in the caption.
"Happy birthday beautiful @kourtneykardash!!!" the mom-of-six wrote.
"From the day you were born you have blessed me with so much joy! You bring happiness love and light and are such an inspiration to me, and everyone around you."
"You are such an incredible mother, sister, friend, and daughter and I love you more than words can ever say.... you are beautiful inside and out my sweet girl, have an amazing day, mommy xoxo #love #family #grateful #happybirthdaykourtney," she added.
Kim, 36, and Khloe, 32, shared similar sentiments about Kourtney online. Khloe also posted a video set to the Stevie Wonder song "Happy Birthday."
"Happy Birthday to the best older sister," Kim said on her website. "I'm so blessed to have you in my life. I love how close we were growing up -- and still are today. I don't know what I would do without you! Love you!"
"Happy birthday to the Milly to my Vanilli @kourtneykardash," Khloe wrote.
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