Claim: Vito Corleone has sons including Sonny and Fredo.

Vito Corleone is a fictional character in Mario Puzo 's novel The Godfather and in the first two of Francis Ford Coppola 's three Godfather films , in which he was portrayed by Marlon Brando in The Godfather and then , as a young man , by Robert De Niro in The Godfather Part II . He is an orphaned Sicilian immigrant who builds a mafia empire . Upon his death , Michael , his youngest son , succeeds him as the mafia don of the Corleone crime family .   He has two other sons , Santino -LRB- Sonny -RRB- and Frederico -LRB- Fredo -RRB- and one daughter Constanzia -LRB- Connie -RRB- . He informally adopts Sonny 's friend , Tom Hagen , a lawyer and his consigliere .   Vito oversees a business founded on gambling , bootlegging , and union corruption , but he is known as a good , generous man who lives by a strict moral code of loyalty to friends and , above all , family . He is also known as a traditionalist who demands respect commensurate with his status ; even his closest friends refer to him as `` Godfather '' or `` Don Corleone '' rather than `` Vito '' .