Johnson & Johnson heiress Casey Johnson died of natural causes related to diabetes, according to the Los Angeles County coroner, CNN reports.

Johnson, who was found dead on January 4 at age 30, was killed by diabetic ketoacidosis, a complication of untreated diabetes. She was best known as reality star Tila Tequila’s fiance, and for her friendships with other wealthy Hollywood progeny like the Hilton sisters and Nicole Richie. Her father, Woody Johnson, also owns the professional football team the New York Jets.