Sarah Kemp Brady, who became an activist for gun control after her husband was shot in the head in the assassination attempt on President Ronald Reagan, has died.  In an email, relatives said Brady died Friday in a retirement community in Alexandria, Virginia, after battling pneumonia.  She was 73.  Brady’s husband, former White House Press Secretary James Brady, of Centralia, died August 4, 2014 also at the age of 73.  Sarah Brady became involved in gun control efforts in 1985, four years after the shooting, which left James Brady partially paralyzed.  She chaired Handgun Control Incorporated, which was renamed the Brady Campaign to Prevent Gun Violence as a tribute to the Bradys.  Sarah Brady’s family said her work has saved countless lives.