premise: Fidel Castro has a brother called Raúl Castro.
hypothesis: Fidel Castro . After a year 's imprisonment , he traveled to Mexico where he formed a revolutionary group , the 26th of July Movement , with his brother Raúl Castro and Che Guevara . In 2006 he transferred his responsibilities to Vice-President Raúl Castro , who was elected to the presidency by the National Assembly in 2008 . Raúl Castro . After his brother Fidel Castro took power , Raúl Castro was one of the most important figures in the party , serving as Minister of the Armed Forces for 49 years , from 1959 to 2008 making him the longest serving minister of the armed forces .