Reality star Kristin Cavallari has marked the first anniversary of her brother's death with a touching tribute online.

The former The Hills star was left devastated a year ago (Nov15) when the body of her sibling Michael was found by law enforcement officers, weeks after he was reported missing in Utah.

His cause of death was listed as hypothermia following a late November, 2015 car crash in Grand County.

On Monday (28Nov16), Kristin took to Instagram to pay tribute to her big brother, admitting her Thanksgiving holiday had been tinged with sadness.

"The last few days have been tough... yesterday was the anniversary of my brother's passing," she captioned a close-up snap of Michael with one of her sons. "There hasn't been a day that's gone by where I haven't thought of him and missed him."

"I know he is watching over me and my family though from all of the amazing signs he has given us," she continued. "Love and miss you so much, Mikey."

Kristin had become a mom for the third time to baby girl Saylor just days before Michael's disappearance, and she previously credited her daughter, who turned one last Wednesday (23Nov16), with helping her cope with the tragedy.

"It's been tough, it has, but I had my daughter Saylor about the same time that my brother passed away so I really just found a lot of strength in my children," she explained to U.S. breakfast show Good Morning America in March (16).

The loss made the former Laguna Beach star reflect on how lucky she is to have a strong support system in her husband, American footballer Jay Cutler, and their relatives.

"When you lose someone that you love, it obviously makes you realize how precious life is and so I've just been thankful for my family and everyone in my life," she added.

Kristin and Jay, who wed in 2013, are also parents to sons Camden, four, and Jaxon, two.