"I tell my daughters, 'What sets you apart is what you are willing to do for others. Anyone can put on a dress and makeup. It's your mind that will define you," she said in Elle's March issue. "Find out who you are, what you think, and what you stand for. And fight for others to have those same freedoms. A life of service is worth living."Two of her daughters, Shiloh, 11 and Vivienne, 9, joined her for the photoshoot with the magazine. (Jolie is also mother to Knox, 9; Zahara, 13; Pax, 14; and Maddox, 16.) Jolie, a goodwill ambassador and UN special envoy, has worked to achieve women's rights on a global scale for many years and co-founded the Preventing Sexual Violence in Conflict Initiative in June 2012. The actress graced the cover of Elle in honor of International Women's Day, which takes place March 8. For the issue, she sat down with former Secretary of State John Kerry, for a wide-ranging discussion that touched on activism, the climate and politics. Jolie admitted that though she was "quite anti-politics" in her younger years, she soon discovered that her humanitarian efforts were best served by working with lawmakers. "I also had this romantic idea that I would get my boots on and be a humanitarian. But at a certain point, you realize that's not enough," she said. " You have to find the root of the problem. And that, so often, brings you back to the law and politics."