"Twilight" Co-Star Taylor Lautner Defends Kristen Stewart Everyone seemed to have an opinion about Kristen Stewart after the Internet exploded with the news that she cheated on her boyfriend and co-star Robert Pattinson with her "Snow White and the Huntsman" director Rupert Sanders, who was married. Still, another co-star of hers, Taylor Lautner, in an interview in the December issue of Cosmopolitan, said he's "proud of her" despite the public backlash, later adding, "Kristen is fantastic at everything she does." RELATED: Kristen Stewart, Robert Pattinson, and 4 More Questionable Couplings The 20-year-old heartthrob also dished on whether he's ever cheated. "To be honest, I've never been involved in any of those situations," Lautner said. The "Twilight" star also said that he still keeps good relationships with all of his exes, which include pop princess Taylor Swift. "I'm extremely thankful for that," he said.