Yes... Raul Castro was Fidel's younger brother... They also had another brother, Ramon, and he was the oldest Castro brother.
No.
Yes, Raul Fidel is Castro's brother.
I think It is Fidelito Castro if you don't believe me ill put a link of where it says its in one of the paragraphs where it says his son Fidelito Castro.
No, Pancho Villa was a Mexican from Durango. Fidel Castro is a Cuban from Birán.