Kris Jenner’s sister, Karen Houghton, has died.

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.