Cause Of Death Revealed For Kris Jenner's Sister Karen Houghton

The cause of death for Kris Jenner's sister, Karen Houghton, has been revealed nearly a month after her unexpected death at 65.

According to a death certificate recently obtained by TMZ, Houghton passed away March 18 due to heart issues, with the report listing cardiac arrest and sudden cardiac arrhythmia as her cause of death. Her Type 2 diabetes was also listed as a secondary, underlying cause, and the doctors noted that she had bipolar disorder.

Jenner, 68, announced "with the heaviest heart and deepest sadness" last month that Houghton had passed away "unexpectedly." She penned a heartfelt tribute on social media, sharing photos of Houghton throughout the years as Jenner mourned her younger sister.

"Karen was beautiful inside and out. She was the sweetest, kindest, the most sensitive and vulnerable and so so funny," the Kardashian-Jenner matriarch said. "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."

She continued, "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."

Houghton's 26-year-old daughter, Natalie Zettel, also shared an emotional tribute to her mother after her death, per E! News.

"You were my best friend, my everything," she wrote in a March 20 post on Instagram. "The best mother a daughter could ever ask for and I'm so grateful to have had a mother like you."