"The Hills" star Kristin Cavallari recently broke her silence about her missing brother Michael Cavallari, who had been missing since the day after Thanksgiving when his vehicle was found abandoned in Utah.

While investigations continue for the search of Kristin's brother, the reality star and fashion designer finally broke her silence and posted on social media, giving thanks to all the supporters of their family in this difficult time.

"I appreciate all the concern, thoughts, and prayers that have been extended to me and 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," Cavallari wrote on Instagram alongside a throwback photo of her and Michael by the beach.

On Dec. 5, the Grand County Sheriff's Office in Utah released a press statement regarding an abandoned 2014 Honda Civic found in approximately 100 feet off the Floy Wash Road, which is just five miles south of exit 175 on I-70 in Grand County, the statement said as posted on the office's official website.

The statement further revealed that the things inside the vehicle led the authorities to identify that the vehicle's driver was Michael, Kristin's brother. "Credit card transaction receipts also led investigators to a convenience store in Monticello, Utah. Upon reviewing the security footage from the convenience store, the driver of the vehicle was positively identified as Michael Cavallari," the statement reads.

Meanwhile, the latest developments in the search for Michael were revealed to be not signifying any criminal offense. "There's no sign of foul play that we can tell," Sheriff Steven White of the Grand County Sheriff's Office told the Today Show. "We're still piecing everything together," White added.

People speculates that Michael has been known to be a troubled individual within his family. "Her brother was always a troubled kid and there was always drama with him," a source told the publication.

The publication revealed that Michael was even arrested days before his disappearance and was briefly held in an Orange County jail last Nov. 23.

"He gave his parents a hard time. He's completely opposite to Kristin who is levelheaded and business orientated," the source added.

As with Kristin, the source told that "She was always very protective of him. She was always trying to help him. He had been trying to produce reality shows awhile ago, but it didn't work out."

Furthermore, the authorities ask that anyone with information regarding Michael's whereabouts is asked to contact the Grand County Sheriff's Office at 435-359-8115.