Unhealthy rivalry between siblings can cause a nasty divide. But luckily for sisters Kate and Mara, they'll never have to worry about that happening. When Rooney was asked by Entertainment Weekly if there is any competition between her and older sister, Kate, the actress responded: "No, because we're so different. I was going out for things completely different from her. We're so different we would never be up for the same part. I never felt anything but support from her. It's nice to have someone who can relate, who you can honestly talk to and has your back." Yeah, we can't really see Kate playing Lisbeth Salander in "The Girl With the Dragon Tattoo," either.