In The Godfather, Don Corleone’s adopted son and family lawyer is Tom Hagen.
Hagen is played by Robert Duvall and serves as the Corleone family’s consigliere. Although he is not Italian, Vito Corleone raises him as part of the family after Sonny finds him living on the street as a child.
The character is sometimes confused with Vito’s biological sons, particularly Sonny or Michael. Hagen’s professional role is also distinct from that of the family’s criminal soldiers: he handles negotiations, legal matters, and sensitive communications.
Tom Hagen continues to appear in The Godfather Part II, although he is absent from most of The Godfather Part III because Robert Duvall did not return for the film.