Casey Johnson

Casey Johnson, the heiress to the Johnson & Johnson fortune to whom internet celebrity Tila Tequila claimed to be engaged, has died, TVGuide.com has confirmed.

The Los Angeles County Police and Fire Departments both responded to what they call an "ambulance death investigation" at 11:51am. The LAFD pronounced Johnson dead at her home on Monday morning.

Tila Tequila engaged to Johnson & Johnson heiress

"It appears to be a natural death," said Officer Sara Faden of the LAPD. "There's no evidence of foul play. Of course, there will be a toxicology report from the coroner's office." Johnson's body is currently at the coroner's office.

Johnson, 30, was the openly gay daughter of New York Jets owner Woody Johnson and the great-granddaughter of the founder of the pharmaceutical giant. "The Johnson family is mourning its tragic loss, and asks for privacy during this very difficult time," a family spokesperson said in a statement.

At the age of 8, Johnson was diagnosed with diabetes. At 14, she co-wrote a book with her father called Managing Your Child's Diabetes. Johnson later appeared in shows like The Fabulous Life of... and E! True Hollywood Story. More recently, Johnson was arrested on charges of grand theft auto. In December, Tequila, whose real name is Tina Nguyen, said that she was engaged to Johnson.

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Johnson is survived by a daughter, Ava, whom she adopted from Kazakhstan in 2007.