Kristin Cavallari shares throwback picture of her missing brother Michael and says she remains 'hopeful' he will be found ten days after his crashed car was found abandoned in the Utah desert

  • Michael Cavallari, brother of reality star Kristin, has been missing since November 27, the day after Thanksgiving
  • Michael's car was found abandoned off a highway in Utah - its airbag had been deployed and the engine was running
  • Sheriffs believe the vehicle had hit a large rock on the side of the road
  • It's believed that Michael was on his way to Illinois from his home in San Clemente, California at the time of the mysterious crash 
  • Kristin Cavallari is married to Chicago Bears quarterback Jay Cutler 
  • The couple welcomed their third child two weeks ago on November 23

Kristin Cavallari says she remains optimistic her brother Michael will be found, ten days after he went missing on a cross-country road trip.

In the former reality star's first statement confirming Michael Cavallari's disappearance on November 27, she thanked her fans for their support during the family emergency.

'I appreciate the thoughts &prayers that have been extended to me & my family. I have such gratitude for those that have shared their support,' Kristin, 28, wrote on Twitter.

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Kristin Cavallari shared this throwback picture of her with her brother Michael to Instagram on Monday (above), amid a desperate manhunt for the reality star's brother in southeastern Utah 

Kristin Cavallari shared this throwback picture of her with her brother Michael to Instagram on Monday (above), amid a desperate manhunt for the reality star's brother in southeastern Utah 

Kristin tweeted her thanks for the support she has been receiving since news of her brother's disappearance

Kristin tweeted her thanks for the support she has been receiving since news of her brother's disappearance

She also shared a throwback photograph of her and Michael as children on her Instagram account. 

Michael was discovered to be missing on Friday, November 27 - the day after Thanksgiving - when his car was found crashed and abandoned off a southeastern Utah interstate.

It's believed that Cavallari was on a cross-country road trip from his home in California to Illinois, where his sister and her husband, Chicago Bears quarterback Jay Cutler, live. 

Just four days prior to the mysterious crash, Kirstin Cavallari gave birth to her third child with Cutler, a daughter named Saylor.  

KSL reported that The Grand County Sheriff's Office received a report on November 27 that a small passenger car could be seen about 100 feet from the Floy Wash Road, five miles from exit 175 on the freeway between Green River and Crescent Junction.  

Michael Cavallari, brother of Kristin
Reality star Kristin Cavallari who is married to Chicago Bear quarterback Jay Cutler

Michael Cavallari (left), brother of reality star Kristin Cavallari who is married to Chicago Bear quarterback Jay Cutler (together, right), was last seen on surveillance footage in a gas station in Monticello on November 27

Michael Cavallari's vehicle (pictured above) was found running with the airbag deployed

Michael Cavallari's vehicle (pictured above) was found running with the airbag deployed

The abandoned car (pictured, with the airbag visible through the windscreen) was found on November 27

The abandoned car (pictured, with the airbag visible through the windscreen) was found on November 27

Police say Mr Cavallari's car hit a rock on the side of the road and then crashed.

The vehicle was found running and the airbag deployed. Cavallari's laptop and cell phone were inside.

'We're combing the area for anything we can find,' White told KSL. 'We're deeming it suspicious but there's nothing to indicate anything one way or another. The vehicle was just abandoned.'

Police identified the car as Michael Cavallari's from credit card receipts that led to the convenience store in Monticello where they saw him in footage on the store's security system (above)

Police identified the car as Michael Cavallari's from credit card receipts that led to the convenience store in Monticello where they saw him in footage on the store's security system (above)

Police identified the car as Michael Cavallari's from credit card receipts that led to the convenience store in Monticello where they saw him in footage on the store's security system.

Grand County is about 100 miles north of Monticello. 

Mr Cavallari went missing just four days after Kristin, 28, and Jay, 32, welcomed their third child, and first daughter, Saylor.

Their first son Camden was born in August 2012, their second son Jaxon was born in May 2014. 

Kristin rose to fame in 2004 as a star on the reality show Laguna Beach, followed by The Hills, with the likes of Lauren Conrad and Heidi Montag.  

Michael went missing just four days after his sister gave birth to daughter Saylor in Illinois (mother and daughter pictured above) 

Michael went missing just four days after his sister gave birth to daughter Saylor in Illinois (mother and daughter pictured above) 

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