VIDEO : Kristin Cavallari's Brother Michael's Death was Due to Hypothermia

Los Angeles - Kristin Cavallari's brother died from hypothermia. Michael Cavallari - the older sibling of the Hills star - passed away two months ago from accidental causes after he crashed his car during extreme temperatures while passing through a rocky and rural part of southern Utah, an autopsy has revealed, according to gossip site TMZ. Michael initially sparked speculation he'd committed suicide after his Honda Civic was found abandoned two weeks after he went missing at the beginning of November. However, his body was later found at the bottom of a steep hillside on 10 December, roughly two weeks after his vehicle was found, about 200 miles south of Salt Lake City.