The Summer I Turned Pretty introduced several cheating story lines in season 3 - and Sean Kaufman is now breaking down the thought process behind Steven and Taylor's infidelity. During an exclusive interview with Us Weekly, Kaufman explained why Steven and Taylor's (Rain Spencer) decision to be unfaithful - with each other - made sense in the context of the show. "I don't condone cheating and I don't think that it's the right thing to do. But I also think that it's a mistake that people make," he said of the fictional couple.