Barbara Bush (above, left) and Jenna Bush Hager share that bond that only twins can. They call each other “Sissy” and are both devoted to social service. Jenna, a contributing correspondent for NBC’s Today show and a UNICEF Next Generation chair, is launching the Novo Project, dedicated to social change. Barbara is the CEO of Global Health Corps, a non-profit that focuses on inspiring and mobilizing young leaders to get involved with global health issues. We caught up with the Bush twins at Barbara’s New York apartment.