Kristin Cavallari is best known as one of the stars of the hit MTV reality shows Laguna Beach and The Hills, but lately her name has been appearing in the news for less glamorous reasons. The reality stars' brother Michael Cavallari, 30, has been missing since the day after Thanksgiving. Cavallari and her husband, Chicago Bears quarterback Jay Cutler, have been keeping quiet about the case for the most part, waiting for news from the authorities. But the stories that keep surfacing about Michael prove that this is no ordinary disappearance. Here's what you need to know about the missing Michael Cavallari:

1) His Car Was Found Abandoned In The Desert
 

The day after Thanksgiving, November 27, marks the last verified sighting of Michael Cavallari. His car was found later that day in Utah, where it appears to have struck a large rock on the side of the road. The airbag had been deployed, and the car was still running when authorities showed up at the scene. His cellphone and laptop had been left behind, apparently untouched. There was no sign of the driver.
 

2) He Was Arrested With A Loaded Gun Just Before He Vanished
 


The days leading up to Michael Cavallari's disappearance were not peaceful ones. Four days before his car was found, Cavallari had an unpleasant run-in with the police in southern California. Authorities said that he was arrested after an unidentified woman reported that Cavallari was standing in front of her apartment with a loaded shotgun. Cavallari denied threatening the woman, although he admitted to having a shotgun in the trunk of his car. Police noted that they could smell alcohol on his breath. Cavallari bailed out of jail two days after the incident, on November 25. Two days later, he vanished.

3) It Was Supposed To Be A Road Trip
 

According to authorities, Cavallari had a long ride ahead of him. After his dramatic departure from California, Cavallari was heading across the country on a lengthy road trip. His final destination was to be Boston. Apparently Cavallari was embarking on the entire trip solo, for no clear reason. Why he detoured through Utah--and what ultimately happened to him--remains entirely a mystery.


4) The Family Has Been Keeping Quiet
 


Despite the increasing urgency of the situation, the Cavallari camp has been remarkly tight-lipped. Kristin has only spoken about her older sibling's disappearance on Twitter, thanking people for their help and support during this trying time. Her husband, Chicago Bears quarterback Jay Cutler, awkwardly fielded a question about his missing brother-in-law during a press conference on Sunday. Aside from that, the family has not been forthcoming with information. Almost all news and leads have come directly from the authorities in charge of the situation--although those have indeed been few and far between.

5) The Search Is Expanding
 


With no hints or clues aside from Michael's car, authorities have gotten serious about the search. Besides people on foot scouring the area where the car was found, police have employed drones to give them an aerial view of the area. Dogs have been called in to sniff out the missing man, who authorities suspect may have been injured during the crash and wandered off from his vehicle. Despite this admirable display of manpower and resourcefulness, there remains no new information.

As Grand County Sheriff Steven White said, "It's like he just vanished."

Tags: Kristin Cavallari Michael Cavallari Reality TV Laguna Beach missing persons