Here's How Kristin Cavallari's Brother Died

The death of Michael Cavallari, brother to reality star Kristin Cavallari and brother-in-law to NFL quarterback Jay Cutler, was accidental, E! reports. Cavallari crashed his car in frigid weather while traveling through a remote part of Utah and died of hypothermia, a medical examiner has determined. He had left California days prior, after being arrested for allegedly threatening a woman with a gun. Toxicology reports are being done to determine whether he had drugs in his system when he died, the AP reports.

Authorities still don't know why Cavallari was in Utah or where he was trying to go, and it's not clear exactly what happened when he died: The 30-year-old was found at the bottom of a steep, rocky hillside two weeks after his still-running car was found abandoned, with its air bag deployed, resting against a small embankment 3 miles away. "I don't know if he thought he saw lights or something and started walking?" the sheriff says. "We just don't know." (More accidental death stories.)