Kristin Cavallari's brother has reportedly gone missing.
Michael Cavallari was believed to have been driving from California to Chicago when his car was found abandoned close to a gas station on the side of a Utah highway on November 27.
The engine was still running and the airbags on the vehicle had been deployed, and though there was no trace of the driver, police found Michael's laptop and cell phone inside.
It is believed the car had hit a large rock.
Local police have made an appeal for information on Michael's whereabouts.
Kristin or her husband Jay Cutler have not yet commented on the news.
The couple recently welcomed their third child, and first daughter, into the world.
Saylor James was born on November 23, just a few days before her uncle's apparent disappearance.
Kristin - who also has sons Camden, three, and Jaxon, 17 months - shared the first picture of her new baby when she was just under a week old, though her face wasn't visible in the image.
She wrote alongside the photo: "Really sad about missing my 10 year high school reunion last night...so many people I wanted to see...but at least I have a good excuse (sic)"