I think th canon is dead...that is the story has been told. Addding to it is like those awful Gone With the Wind sequels.
There is still much to work with and to interpret in the original novel and the three films.
Anything beyond that is The Godfather making a parody of itself.
"Io sono stanco, sono imbigliato, and I wan't everyone here to know, there ain't gonna be no trouble from me..Don Corleone..Cicc' a port!"
"I stood in the courtroom like a fool."
"I am Constanza: Lord of the idiots."
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