I read the book - is this true

Within the pages of The Godfather Returns, and followed up on in The Godfather's Revenge, also by Winegardner, it is stated that Fredo had a child before he died, and the child was given up for adoption by the mother. Also, light is shed upon the fact that Vincent Mancini-Corleone is not the bastard son of Fredo's older brother, Sonny, but in fact, that of Fredo.

it says Vinnie dies Decemeber 17, 1990

somebody needs to edit this wikipedia

http://en.wikipedia.org/wiki/Vincent_Mancini-Corleone

This was also discussed here ( http://www.gangsterbb.net/threads/ubbthreads.php?ubb=showflat&Number=279423&page=1#Post279423 ) at the bottom of the thread.

That's the problem with Wikipedia, anybody can write whatever the hell they want.

Look at the Chris Benoit debacle today.