5. Sonny, Fredo, Michael, Connie. I think that Tom Hagen was around the same age as Sonny.

6. Genco was Vito's consigliere...the same position that Tom Hagen held. I believe that they first met when Vito worked at Genco's father's grocery store, as shown in Part II. Genco dies at the very beginning of Part I (from cancer or something like that) in a deleted scene. And he was also in the whole olive oil business with Vito, the company was actually called Genco Olive Oil.