The Grand County Sheriff's Department has finally determined the official cause of death for Michael Cavallari, brother of former "The Hills" star Kristin Cavallari. His body was discovered in December 2015 after a two week search of the desert in Grand County, Utah. The investigation into his death was initially opened as a potential suicide.

E! News reports that, based on tests run by the Utah State Medical Examiner's Office, Michael, 30, died from hypothermia. The condition was a result of exposure to the elements. Officials told the publication Michael's body was discovered about three miles from his abandoned car. He did not appear to have suffered any injuries and left no sign that the death was a suicide. 

"Michael Cavallari's body was found three miles from where his car was wrecked in the high desert of Grand County, Utah. There were no signs of major trauma and no suicide note," officials said. "Cops did not find any evidence of drugs or alcohol either."

Shortly after news broke of Michael's death, his sister took to social media to share a heartfelt message with fans. On Dec. 10, Kristin, 29, wrote that she was heartbroken to learn that her brother had died, recalling the many laughs they shared during his lifetime. The ex-reality star praised Michael for having "a good heart," adding that she would miss him forever. Within minutes the post garnered thousands of likes from supportive fans. 

Michael's body was found early that same day. As was previously reported, the two week search for Kristin's sibling ended with confirmation from local authorities (via E!) that they had uncovered a body. Kristin later released a statement confirming the report and thanking fans for their unwavering support. She asked for privacy as she and her family coped with their loss, telling the public that this would be an extremely "painful" time for them.