Kristin Cavallari's Brother -- Found Dead

2:45 P.M. PST -- TMZ obtained a police report from Orange County, where Michael was arrested for criminal threats just 5 days before disappearing. According to the report, Cavallari showed up to his girlfriend's apartment with a loaded shotgun after a verbal dispute, and made threats. Cops also say they smelled a strong odor of alcohol on his breath. He was released 2 days later, and then disappeared.

1:23 P.M. PST -- Law enforcement tells TMZ they located remains they believe to be Michael at 10:30 A.M. They say the body was found in a steep and very rocky area.

Kristin Cavallari's brother and Bears QB Jay Cutler's brother-in-law has been found dead in Utah.

30-year-old Michael Cavallari's car was found abandoned November 27th. It appears he wasn't reported missing until 3 days ago.

In a statement to TMZ, Kristin says, "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."

It's unclear how Michael died, but he's struggled for many years with alcoholism and has had more than his share of trouble.