According to law enforcement sources, Karen was reported dead to San Diego County officials on Monday, March 18, in San Marcos, California.
The exact circumstances of her passing are unclear, but county officials are attributing her death to natural causes for now.
Karen was Kris Jenner’s only sister and was born three years after the famous momager.
Karen and Kris grew up in San Diego together, living predominantly with their mother MJ after her divorce from the girls’ father, Robert Houghton.
This is MJ’s first loss of a child and the Kardashian-Jenner family is rallying around each other.
Kris took to social media to address Karen’s death. She shared throwback photos of them together as she mourned her.
Kris wrote: “It is with the heaviest heart and deepest sadness that I share that my sister Karen passed away yesterday unexpectedly. My heart aches for my mom MJ and my niece Natalie and I pray that God guides us all through this difficult time.
“Karen was beautiful inside and out. She was the sweetest, kindest, the most sensitive and vulnerable and so so funny. She always felt grateful and thankful for her life and treasured her family and friends and especially her beautiful daughter. She holds such a huge part of my heart and I cherish every single memory we have together.
“Karen’s passing is a reminder that life is so short and precious and tomorrow is never promised. We must tell those we cherish how much we love them. I love you my beautiful sister.”