Kristin Cavallari
Former "Hills" star Kristin Cavallari, pictured Oct. 23, 2014, took to Instagram Thursday to express her grief over the death of her brother, Michael. Getty Images

Former “Hills” star Kristin Cavallari wrote a heartbreaking message to her brother, Michael Cavallari, after he was confirmed dead Thursday. The former reality star, who is married to Chicago Bears quarterback Jay Cutler, took to Instagram to express her grief over his untimely death.

“My heart is in a million pieces,” she wrote to her 1.6 million followers. “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 [you] are in a better place and finally at peace. I love u [sic] so much, RIP.” She finished the post with an emoji of a broken heart.

Kristin Cavallari, 28, has the support of her fans. Thousands of Instagram users liked the image minutes after she shared it on social media.

Michael Cavallari
Michael Cavallari, pictured above in a photo provided by the Grand County Sheriff's Department, has been confirmed dead after he was missing for nearly two weeks. Grand County Sheriff's Department

Further details about what happened to Michael, 30, have not been revealed. His cause of death is currently unknown.

He was missing for nearly two weeks before his body was found by the Grand County Sheriff’s Office in Utah. Michael was reportedly en route to Illinois when he vanished. Officers discovered his car five miles south of Interstate 70, off Exit 175 near Green River, Utah, Nov. 30. The vehicle was still running, and one of the airbags was deployed.

Kristin Cavallari issued an official statement about the tragic news earlier in the day and thanked her fans for their support. "We want to thank everyone for their love, support and prayers during this very difficult time," she told E! Online. "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. We kindly ask everyone please respect our privacy during our time of grieving."

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