EXCLUSIVE: Kristin Cavallari looks lost in grief as body of missing brother Michael is found at bottom of steep, rocky slope three miles from where he abandoned his car with the engine running

The brother of reality star Kristin Cavallari was found dead some three miles from where he abandoned his car in the Utah desert.

Michael Cavallari’s body was discovered by searchers at approximately 10.30 this morning three miles north west of his vehicle, towards the bottom of a rocky slope. 

The 30-year-old appears to have been walking back towards the I-70, the highway he inexplicably left with such disastrous consequences.

But his wandering took him further into the desert, away from the dirt track he had taken - either in error or in an inexplicable moment of misjudgement - when leaving the I–70 at exit 175.

Cavallari drove more than five miles down a dirt track but had turned back to head towards the highway once again when he careened off the rubble strewn path, coming to a halt in rocky, heavily rutted ground some 100 feet from the road. 

His airbags had deployed and the engine of his car was still running when it was discovered on the morning of November 27.

Speaking exclusively to Daily Mail Online Grand County Sheriff Steven White revealed: ‘We found him north west of where the car was located approximately three miles from the vehicle.’ 

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In a moving post on Instagram she paid tribute to Michael saying 'My heart is in a million pieces'

Disappeared: Kristin Cavallari's (right) brother Michael (left) has been discovered dead after he went missing in Monticello, Utah. His body was found three miles away from where he abandoned his car 

Running errands: Kristin Cavallari is pictured walking around Chicago on Thursday - the day her brother was found dead

Last seen: These tire tracks are where Michael Cavallari left his Honda Civic after careening for about 100 feet on the dirt road behind - which is itself five miles off the interstate he would have traveled on

Remote: How Cavallari's journey unfolded. A map shows where Michael went in the build-up to his death 

He described the location of the body, in an area known as Salt Wash, as ‘a very steep slope, kind of rocky with boulder fields around it.’

Sheriff White said: ‘He was kind of on the slope itself, he was not too far from the bottom but he was actually on the slope itself.’

Referring to the distressing discovery which comes 14 days after Cavallari vanished into the Utah desert Sheriff White said: ‘We had a large group of thirty plus people searching out there. We found him at approximately 10.30 this morning. It was a tough day.’

Cavallari’s body has been sent to the Medical Examiner to determine time and cause of death. Toxicology results may take up to 8 weeks to come back.

Sheriff White added: ‘I’d like to send my condolences to the family. This is a tough situation. But there were multiple agencies that assisted this and a lot of people who put in dedicated time and I’d like to thank them for bringing closure to this.’ 

Kristin confirmed that Michael's body had finally been found in a heartfelt post on Instagram on Thursday.

'We have just been informed by the authorities my brother's body has been found,' she told People '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 paid tribute to her troubled older brother 'Mikey.'

'My heart is in a million pieces,' she wrote. 'Mikey, I could always count on you to make me laugh. 'You had such a good heart and will be forever missed.

'I'm at a loss for words but I know u are in a better place and finally at peace. I love u so much RIP.'  

Detectives had been searching for Cavallari since November 27 after his 2014 Honda Civic was found abandoned five miles south of exit 175 on I-70.

He was last seen at Maverick gas station in Monticello, 100 miles south from where his car was abandoned. It was 3.30am. He bought gas and asked for directions to Salt Lake City before getting on the 191 north.  

On Monday, Kristin, 28, had uploaded an Instagram picture of herself and her brother as children with a now tragic message which read: 'We remain hopeful … I have such gratitude for all those that have shared their support.'

Glum: At points Kristin walked with her head down and stared at her feet

After news of Cavallari's death, she thanked everyone for their 'love, support and prayers during this very difficult time,' People reports.

The loss of her older brother is likely to take a huge toll on The Hills star who has just given birth to her third child. 

Thirty officers have been involved in the painstaking search which saw them re-combing an area of two square miles, desperately hoping to find some clue so far overlooked. Cavallari's father and stepfather had traveled to Utah to help efforts but have since returned home to California.

Only yesterday, the hunt had still been well underway, with Grand County Sheriff Steven White, 46, saying: 'We're basically looking for him or any sign of him – any article he may have dropped that kind of thing.'

Sheriff White had been hopeful that somebody might have picked up the beleaguered Cavallari and driven him away from the area.

It is just one of 'about two dozen' theories on which Sheriff White and his officers were working on before his body was discovered. 

The Hills star has just given birth to her third child. Her brother Michael had not been seen since November 27, when his car was abandoned on an interstate in Utah 

Cavallari, who is married to Chicago Bears quarterback Jay Cutler, plays with a lanyard as she walks through a park. After hearing news of her brother's death, she thanked people for their support on social media 

Pensive: The former reality star wore a large winter coat and looked pensive as she strolled in the Windy City 

Memories: Kristin shared a childhood photo of herself and Michael on the beach on Monday on her Instagram page

Happier times: Today Kristin shared another picture of herself and Michael as children paying tribute to her brother

Another was that, dazed from his crash, Cavallari may have set out not knowing where he was going and wandered into the desert. 

According to Sheriff White: 'Then you're looking at hypothermic conditions.'

Officers retracing Michael's last steps, say that after he left the gas station, he drove through the small town of Moab – population 5,000 - 60 miles south from where his car was found and the last civilization he would have seen on his journey that morning.

Close to two hours into his drive North West towards Salt Lake City, Cavallari took the first exit he came upon on the I-70, exit 175.

Either way his reason for leaving the highway is unknown and what he did next was either a terrible mistake or an inexplicable decision.

Faced with a T-junction at the top of the exit ramp he turned left towards Green River. He then kept driving straight, though the paved road runs out after less than two miles giving way to a rubble strewn dirt track along which his Honda Civic would have labored and on which restricted access signs are regularly posted.

He drove more than five miles along the track that took him deeper and deeper into the inhospitable desert. Close to the highway cattle roam but further inland there is nothing but coyotes and the occasional antelope as the road heads towards Canyonlands National Park.

According to Sheriff White: 'It just doesn't make any sense. We don't know if he'd been drinking or what his state of mind was.' 

But at some point Cavallari either changed his mind or realized his mistake. 

He turned his car and was heading back towards the highway when, either distracted, asleep or drunk at the wheel, he missed a curve in the hazardous road and careered off the track, rumbling some 100 feet into the scrubland before nose-diving into a deep hole.

Baffled: Grand County sheriff Steven White tells Daily Mail Online of his decision to drive a Honda Civic up a dirt track: 'It just doesn't make any sense. We don't know if he'd been drinking or what his state of mind was.'

Back-country: The Grand County sheriff has been deploying off-road vehicles to search ground which is frozen by night but muddy by day. There are frequent coyote sightings

Last seen: Security camera showed Michael Cavallari filling up with gas at this station in Monticello. His car was found about 100 miles drive away hours later with the engine running

Winter: Temperatures in the area fall below freezing every night and it is also coyote country. A bear was sighted on the north side of I-70. Cavallari was to the south of the interstate

'We're not sure if maybe he fell asleep or was distracted, if he was reading a map or something because you can see where he missed the curve and the tire tracks that ride straight out there,' said White. 

It is not yet known how Michael died, but he faced a harsh, unforgiving environment when he wandered, or perhaps fled fearing another DUI, into the wilderness.

Snow is scattered on the ground, small pockets of water and ponds stand frozen and the scrubland and rocky outcrops provide no shelter.

Predators roam, with the call of coyotes echoing through the desert nights and a bear sighting was recently reported on the other side of the I-70.

Among the many challenges facing law enforcement trying to make sense of the evidence they have so far – a running car, its airbags deployed, laptop and phone left behind – is the fact that they are unclear as to Cavallari's state of mind at the time of his crash.

Daily Mail Online revealed that Cavallari was recently kicked out of his father's home in San Clemente, California for his struggle with alcoholism and psychological issues that saw him acting 'crazy.'

Until recently troubled Cavallari spent his days chain smoking and drinking heavily while playing online poker inside his father's $6.6million home. He refused to find a job and it's believed to have depended on his father, Dennis, a wealthy commercial property developer, for financial support.

Earlier in the week: Kristen had a smile on her face as she walked around with her son on Tuesday 

Fleeing? Dana Point in California, just beside San Clemente. Cavallari was arrested here four days before he went missing

Home: The house where Michael Cavallari lived with his father in San Clemente, California. His behavior disturbed his father's tenants

Last stop: The direction of travel showed that Cavallari had turned back towards I-70, which he would have come off to get onto the dirt road 

Questions: He asked for directions to Salt Lake City and his abandoned car was found hours later in Grand County

Search under way: The local sheriff's department has search teams in place but is holding out hope he made it to a recreational area over the mesa to the rear

Dennis' one-acre property, which sits just five blocks from the beach in picturesque coastal town San Clemente, has guesthouses on site that he rents out.

According to one source close to the family, Cavallari's alcoholism and unpredictable behavior angered the tenants who repeatedly complained to Dennis.

Neighbors also reported hearing regular commotion at the property including visits by the police.

One neighbor of Cavallari recalls seeing him wandering around the back yard shouting, 'the CIA is coming to get me'.

The neighbor, who asked not to be named said: 'Michael would come over early in the morning, around 7am, and ask me if I wanted to drink a beer with him, which was a little odd.

'When I refused he'd get mad. Then I remember a few times we'd see him ranting in the back yard, shouting that the CIA was coming to get him. He seemed paranoid, completely out of it.

'It's sad really, he obviously had an lot of issues going on.'

Other neighbors on the street recall an incident earlier this year in the early hours of the morning during which Michael and his girlfriend were heard screaming at each other during a blazing row.

Eventually, just a few months ago, Dennis, 63, was forced to kick his son out of the home.

The source said: 'Michael is a very difficult person to get along with; he's not all there, crazy.

'He had a room in his dad's house but he was always a huge disturbance to his father's tenants.

'He would play loud music, club bass, until three in the morning, it made one of the tenants very angry, they almost came to blows.

Last sighting: CCTV at a gas station in Monticello, Utah, picked up the last known sighting of Michael Cavallari

'The police were also called out when he had an argument with his girlfriend in the street, there was always some drama.

'The tenants complained to him and to his dad but it didn't stop. Michael and his father also had their own issues and Dennis had no choice but to kick his son out because he was upsetting the paying tenants.

'The tenants were like 'it's us or him' and Dennis totally understood, he had to go.

'Michael was a heavy drinker, I'd say alcoholic, and smoked a lot, he was a bad bad dude, just crazy.'

The source said Cavallari, who had lived with his father for around a year and a half, moved out around two to three months ago.

'Dennis definitely babied him and that was a huge problem for his past relationship with his wife. They had a lot of issues,' the source added.

Michael and his father also had their own issues and Dennis had no choice but to kick his son out because he was upsetting the paying tenants

'But Dennis always had a huge soft spot for his son so has looked after him over the years.

'But he wasn't doing anything with his life, just lounging around and playing online poker.'

In a further disturbing revelation it has transpired that Cavallari's disappearance came four days after his personal life appeared to spiral out of control.

He had been arrested for making criminal threats against a woman on November 23 - the same day his sister Kristin gave birth to her daughter Saylor.

According to a report in US Weekly authorities were dispatched to Dana Point, California, after a woman reported seeing him outside her apartment with a shotgun.

The two had reportedly had a dispute earlier that month, after which he knocked on her door for 'several weeks'. She called the police, but did not file charges.

According to the department, deputies arrested Michael after he admitted to having a loaded shotgun in his trunk and additional ammo was found at his home.

The sheriff's office says he denied 'doing anything or saying anything' to the woman.

Michael was previously arrested for DUI in November 2014, and received three years probation.

Grand County Sheriff's Department said it was taking every detail of Cavallari's troubled life into consideration as they attempt to resolve this case.

Sheriff White said early reports showed that Cavallari appeared to have been just travelling through Utah, according to family and friends. 

There were no signs of foul play at the car, he said, but he added, 'Right now we're not ruling anything out. '