Kris Jenner Shares Tribute for 'Beautiful' Sister Karen After Sudden Death: 'My Heart Aches'

Kris Jenner is mourning the loss of her younger sister Karen Houghton after her sudden death at age 65.

In a tribute posted on Instagram on Tuesday, the Kardashians star, 68, announced that her sister had died "unexpectedly" the day before.

With "the heaviest heart" and the "deepest sadness," Jenner shared a carousel of images spanning throughout their lifelong sisterhood. They included baby photos, self portraits and moments from various family events.

"My heart aches for my mom MJ and my niece Natalie and I pray that God guides us all through this difficult time," she captioned the post. "Karen was beautiful inside and out. She was the sweetest, kindest, the most sensitive and vulnerable and so so funny."

The famed momager went on to describe her sister as someone who was "grateful and thankful" for her life and treasured not only her family and friends but "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," she concluded. "I love you my beautiful sister."

Jenner's mother Mary Jo "MJ" Shannon was previously married to Robert Houghton — with whom she welcomed the reality star at age 20 and Houghton shortly afterward. Shannon's marriage to Houghton was short-lived and the matriarch raised her two daughters as a single mom before she met and married her third husband Harry Shannon.

MJ and Harry’s union lasted for 40 years, up until his death after a car crash in 2003.

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Though he was her stepfather, Jenner revealed in a 2015 Haute Living profile that she considered Harry to be a father figure. She previously referred to him as "my dad" while acknowledging that his death “was so devastating for my family.”