‘RHOSLC’ Star Mary Cosby’s Son Robert Cosby Jr. Passed Away At 23

Feb 25, 2026 at 2:00 pm | By Dru Marie Allen

Credit: Bravo

Just days ago, Mary Cosby’s son Robert Cosby Jr passed away tragically at the age of 23. The devastating news comes after he has opened up about his struggles with addiction on The Real Housewives of Salt Lake City.