Update, 12/11: Kristin Cavallari's brother Michael likely died from exposure to cold, law officials tell E! News.

Sources told the site, "Michael Cavallari's body was found three miles from where his car was wrecked in the high desert of Grand County, Utah." Michael had abandoned his car for unknown reasons in late November, and temps in the area reportedly fell to the teens at night. 

"There were no signs of major trauma and no suicide note," officials said. "Cops did not find any evidence of drugs or alcohol either." Toxicology reports are expected to paint a clearer picture within 6-8 weeks.

Kristin has posted a tribute to her brother on Instagram, which you can see below. "My heart is in a million pieces. 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 💔" she wrote.

Kristin Cavallari's brother Michael was found dead on December 10, less than two weeks after he was first reported missing.

Cavallari released a statement to PEOPLE, saying, "We want to thank everyone for their love, support and prayers during this very difficult time. 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."

A cause of death is currently unknown.

Original story appears below.

Former reality star, actress and ladies' accessories designer Kristin Cavallari is remaining hopeful as the search for her missing brother, Michael Cavallari, continues.

On the night after Thanksgiving (November 27), authorities located Michael Cavallari's 2014 Honda Civic abandoned on the side of the road along a Utah highway, People reports. The car was apparently left running, the airbags had been deployed, and Michael's cell phone and laptop were found inside. Police in charge of the case are now treating it as an open missing person investigation, although they recently admitted to the Today Show that they are "still piecing everything together" and do not suspect foul play at this time.

Fans have come together to support Cavallari and her family in their search for Michael, and earlier Monday morning (December 7), Kristin reached out to them to express her gratitude. The post features a picture of her and her brother when they were younger, embracing on the beach, as well as a caption that says, "I appreciate all the concern, thoughts, and prayers that have been extended to my family. We remain hopeful and I will share any news that we receive. I have such gratitude for all those that have shared their support."

Anyone with information regarding the case is encouraged to contact the Grand County Sheriff's Office at 435-359-8115.

Our thoughts are with the Cavallari family.

Show Your Support for These On-Again Off-Again Couples