Teenager Malala Yousafzai — who earned a Nobel Peace Prize for promoting the rights of girls — now holds the highest honor bestowed by the U.N. chief on a global citizen. “It is important for girls to realize that their action and their voice is important, and it is needed right now,” the 19-year-old said after an April 10 ceremony where she was officially designated a U.N. Messenger of Peace. She is the youngest person to be so honored.