While Kristin Cavallari is living her life as a single parent, some critics have a bone to pick with her. 

Fortunately, the star's best friend has her back. On Sunday, Jan. 10, the mom of three posted a photo of herself laughing with girlfriends, sarcastically captioned "Zero fun." Well, it was zero fun in the comment section after one naysayer criticized the TV personality for allegedly never having her kids with her.