Original: Robert Francis '' Bobby '' Kennedy ( November 20 , 1925 -- June 5 , 1968 ) , also referred to by his initials RFK , was an American politician , a Democratic Senator from New York , and a noted civil rights activist .
Simplified: Robert Francis '' Bobby '' Kennedy ( November 20 , 1925 -- June 6 , 1968 ) , also called RFK , was the brother of former U.S. President John F. Kennedy .