Kardashian Family Tragedy: Kris Jenner Reveals Her Sister Karen Died 'Unexpectedly'

Kris Jenner revealed she lost her sister Karen Houghton suddenly.

"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," the matriarch, 68, captioned a slew of photos via Instagram on Tuesday, March 19.

Of course, people sent the reality star well-wishes after the tragedy. One person wrote, "So sorry for your loss. Sending you and your family so much love. ❤," while another said, "Oh my goodness, our deepest condolences, sweetheart for your loss. May she rest in peace. You have another angel watching over all of you you’re in all of our prayers and thoughts.💔💔💔💔💔💔@krisjenner."

A third person added, "My deepest condolences to you and your family. Much love. ❤."

Houghton's death has not been disclosed, but TMZ reported that she likely died from natural causes.

Though Jenner spoke highly of her sibling, the two were apparently once estranged , RadarOnline.com reported.

“Pray for Kris Jenner she needs it…crazy,” Houghton wrote via Facebook in April 2014. "Shes as [sic] nutcase. She doesn’t need prayers she needs sky vodka hahaha hahaha hahaha.”

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“If you think your sister would call you back, she doesn’t,” she claimed at the time. “And it hurts me. I don’t care how much money you have or who you are, you’re my sister. I’m not afraid of her. … I can’t get to her anymore. But I guess it’s the money.”

Houghton also said her sister was "serious" and not "warm and fuzzy."