In a video posted to Cavallari’s Instagram on Sunday (November 17), she and her friend Justin Anderson did the “Suspect Challenge” trend, where one person described as the “suspect” is filmed jogging while the cameraperson mocks them for previous decisions they’ve made.

Kristin Cavallari’s best friend Justin Anderson exposed who the reality star’s “hottest hookup” was with while they filmed the “Suspect Challenge” TikTok trend. In the video shared Sunday, the pair jogged next to each other and alternated roasting each other with a quick sentence.

Kristin Cavallari's secret is out in the open — thanks to her pal! On Sunday, November 17, the Laguna Beach alum joined her friend Justin Anderson for a playful take on the viral “suspect” trend, where participants jog while revealing surprising or humorous truths about each other.