Barbara Bush helps a nun to fit on a hearing device during a 2012 event in Gulu, Uganda. She says was interested in architecture as a college student but became a global health activist after visiting East Africa with her parents. Reuters/Landov hide caption

itoggle caption Reuters/Landov

President Barack Obama gestures toward former President George W. Bush, former first lady Laura Bush and first lady Michelle Obama, at the White House in Washington, Thursday, during a ceremony where the Bushs' portraits were unveiled. Charles Dharapak/AP hide caption

itoggle caption Charles Dharapak/AP