Michael Cavallari, Kristen Cavallari’s brother, believed to be found dead in Utah

Investigators believe they found the body of reality TV star Kristen Cavallari’s brother on Thursday in Utah, authorities said, three days after he had been reported missing.

A body believed to be Michael Cavallari was found at about 10:30 a.m. by search crews in an area off an interstate there, according to the Grand County Sheriff’s Office. He was found in a steep and rocky area not far from where his car was last seen, which is about four hours southeast of Salt Lake City.

“My heart is in a million pieces,” Kristen Cavallari posted on Instagram late Thursday afternoon along with a photo of the siblings as kids. “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.”

On Nov. 27 Cavallari’s car, a 2014 Honda Civic registered in California, was found about 100 feet off the road in Grand County. Investigators matched him to the car from a surveillance video at a convenience store in Monticello, Utah, about an hour south of where the vehicle was discovered.

Cavallari’s sister was a cast member on “Laguna Beach: The Real Orange County” and “The Hills” and is married to NFL quarterback Jay Cutler.

On Dec. 7 Cavallari posted another photo of herself with her brother, saying she was grateful for “the thoughts & prayers” as investigators searched.