Reality star Kristin Cavallari said in a statement Thursday that the body of her brother has been found.
"We want to thank everyone for their love, support and prayers during this very difficult time," Cavallari said in a statement to E! Online. "We have just been informed by the authorities my brother's body has been found. This is a very painful time and we are still processing it all. We kindly ask everyone please respect our privacy during our time of grieving."
She also posted on Instagram about her late brother, saying: "My heart is in a million pieces. Mikey, I could always count on you to make me laugh. You had such a good heart and will be forever missed."
Utah authorities confirmed Thursday that search crews located remains believed to be of Michael Cavallari at 10:30 a.m. in a steep and very rocky area in Grand County near exit 175 on I-70.
The body was being taken to the Utah Medical Examiner for positive identification and to determine the cause of death, the Grand County Sheriff's office said in a news release.
Investigators have been trying to piece together what happened to the brother Cavallari, who hadn't been heard from since his car was found abandoned more than a week ago near a remote dirt road in Utah.
Michael Cavallari, 30, lived in Southern California and was arrested on an allegation of making threats there Nov. 23, authorities said Monday. He was the brother-in-law of Chicago Bears quarterback Jay Cutler, who married Kristin Cavallari in 2013. His car was found empty and still running four days later.
According to a police report, Michael Cavallari was arrested outside California's Dana Point City Hall with a loaded shotgun after a woman called the sheriff's department to say Michael Cavallari had been outside her apartment with a gun.
The unnamed woman told deputies the two had argued days earlier, and she was afraid because he kept returning to her apartment. Police reported smelling alcohol on Michael Cavallari's breath when he was arrested. He acknowledged having a loaded shotgun in his trunk, the report said.
He was taken into custody without incident, and he denied doing anything to the woman, who reported the incidents to authorities. Orange County Sheriff's Lt. Jeffrey Hallock said Monday that Michael Cavallari bailed out of jail Nov. 25.
Four days later, a rancher found Michael Cavallari's car in Utah with its engine running and the air bag deployed, Grand County Sheriff Steven White said. It was about 200 miles south of Salt Lake City and five miles south of Interstate 70, in a part of the state that's home to several national parks.
Cavallari apparently was driving by himself, though it's unclear where he was going, authorities said. Evidence shows Michael Cavallari's 2014 Honda Civic hit a couple big rocks and washes, likely causing the air bag to deploy, according to White.
White said crews have been searching the area on foot and by helicopter but have found no trace of Michael Cavallari. It's difficult to find footprints in the frozen ground, he added. Temperatures in the area have been at or below freezing every night since the car was found up against a small embankment.
There were no signs of foul play.
Hours before his Honda was discovered, Michael Cavallari stopped at a convenience store about 60 miles away and asked for directions to Salt Lake City. Credit card transactions and surveillance video from the store show he was in the town of Monticello at 3:30 a.m. on Nov. 27.
Michael Cavallari works for his father's corporation, White said. He is single and has no kids.
His sister, Kristin, rose to fame in the mid-2000s when she appeared in the MTV reality series "Laguna Beach" and "The Hills." She and Cutler have three children together.
On Monday, Kristin Cavallari posted a photo on Instagram of her and her brother as kids at the beach with a message thanking people for their thoughts and prayers.
"We remain hopeful and I will share any news that we receive," she wrote.
Cutler was a star player at Vanderbilt University and now plays for the Chicago Bears in the NFL. The 32-year-old said little Sunday when asked about whether the situation with his missing brother-in-law was a factor in his team's loss.