I can find no relevant evidence that proves Vincent Mancini was Santino Corleone's son, bastard or otherwise.

In the novel it states that shortly after Sonny was killed, Tom made arraingements for Lucy Mancini to move to Las Vegas where she hooked up with a doctor. Nowhere does it ever say that she was at anytime, pregnant with or had given birth to, a child by Sonny Corleone.

I could go on but typing makes me tired.

Anyone know anything different?