It's a tale as old as time: step-mom versus real mom, new girlfriend versus ex-girlfriend...and A-List celebrities are no exception. The history between Sofia Richie and Kourtney Kardashian is complicated to say the least. After years of being together and having three children as well, Scott Disick and Kourtney Kardashian called it quits in July 2015. Scott began dating Sofia Richie, nearly 16 years younger than Disick. Right off the bat, it is easy to see why there may have been tension between the two.