Michael Cavallari, 30, found dead, sister Kristin Cavallari says to E! News

SALT LAKE CITY, Utah -- Michael Cavallari, the brother-in-law of Chicago Bears quarterback Jay Cutler, was found dead in Utah.

Cutler's wife, Kristin Cavallari, posted a picture of her with her brother as children on Instagram with the words, "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..."

Michael Cavallari, 30, was reported missing two weeks ago. His car was found abandoned in southern Utah the day after Thanksgiving. For several days, teams of officers with search dogs and drones fanned out over the desolate area in Grand County, which is about 200 miles south of Salt Lake City. His body was found Thursday three miles northwest of his car on a rocky hillside.

There were no bullet holes or stab wounds or other signs of foul play.

The frigid temperatures in the area may have factored in, Grand County Sheriff Steven White said. Temperatures in the area were at or below freezing every night since the car was found up against a small embankment.

"I don't know what his mental state might have been, with possible hypothermia," White said.

The Grand County sheriff released a statement: At approximately 10:30 a.m. search crews located remains believed to be that of Michael Cavallari. At this time, the body is being transported to the Office of the Utah Medical Examiner for positive identification and to determine the cause of death. The search crews were searching the Salt Wash area, near exit 175 on I-70 in Grand County. The terrain where the body was located is a steep and very rocky area.

On November 25, Michael Cavallari bonded out of jail after allegedly threatening a woman in Orange County, California. The unnamed woman told deputies the two 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.

Michael Cavallari denied doing anything to the woman.

Kristin Cavallari rose to fame in the mid-2000s when she appeared in the MTV reality series "Laguna Beach" and "The Hills." Cutler played football at Vanderbilt and now plays for the Chicago Bears in the NFL. The couple has three children together.

The Associated Press contributed to this report.