In kicking around the Vito-Tom Hagen relationship, I get a sense that he was partial to Tom in certain ways..even above his own sons. There could be several reasons for this. Both Tom and Vito had similar early childhoods. They pretty much had to fend for themselves, and Vito, when he took Tom in from the street saw himself as a patron to him, and no doubt Tom was ever grateful and appreciative of the opportunity to grow up in a big family, be able to go to college and law school and then return the favor by helping Vito. Also he was more mature than Sonny, smarter than Fredo, and with Michael always rebelling, he was a steady hand. It is obvious that Vito and Tom confided in each other aboutmany things, including about Vito's children. Vito and Tom talked about Michael's future (to Michael's chagrin). They also talked about employing Connie's husband, and no doubt they talked privately about Sonny's temper and womanizing as well as what to do about Fredo. This closeness set up all Vito's sons to be jealous of Tom, and it showed.

Like Michael, Vito was absolutely sure of Tom's loyalty for all those reasons. Sons are sons, but Sonny was the only one of them that Vito employed at all initially in helping with the business. Tom actually asked to work for Vito and Vito obliged him by involving him more and more in the business. I don't think Sonny was jealous. Fredo just silked about it or may have not been intelligent enought o see Tom's closeness to Vito. Michael could have been authentically jealous.

I agree Fedo was probably not bright enough to see it, but Sonny showed it...

Sonny - That's easy for you to say, he's not your father.
Tom - I'm as much a son to him as you or Mike. (Note he omits Fredo....no respect!)

and this

Sonny - Pop had Genco look what I got.
Tom - (looks hurt)
Sonny - I'm sorry, look Mom made a little dinner....

and this

Michael (to Tom) - You talked to MY father about MY future!

DT... you're completely right. I don't know if so much for Santino and Fredo, but for sure the jealousy was evident in Michael!

dt and Olivant: I agree with everything you posted initially. But, while you can never totally dismiss jealousy as a factor in family relationships, I think Michael's attitude had more to do with his controllling and distrusting nature. As we've discussed: Tom was Sonny's choice as a brother, jnot Michael's; Tom was Vito's choice for consigliere, not Michael's. Didn't necessarily mean Michael was resentful or hostile to Tom (though he did show hostility on occasion, as did Sonny)--it meant that someone Michael didn't personally choose or vet was ipso facto not someone he'd get close to.

Keep in mind that in the novel it states that Mike noticed how affectionately Sonny greeted Tom.

"Michael realized with a faint twinge of jealousy that ... Sonny and Tom Hagen were closer than he could ever be to his own brother."

This would make sense on tow fronts: one, Sonny is the one that got Tom off the streets and brought him in, so they would naturally be close, two, Michael did everything in his power up to that point to remain detached from anything having to do with the fmaily business, while Tom was an intricate part of it.

After the discussion between Santino, Tom and Michael, there's a situation described in the novel:

>>As he went out the door he said casually to Hagen, “Do you have in your notes that the Turk made his living from prostitution before the war? As the Tattaglia family does now. Write that down before you forget.” There was just a touch of derision in the Don’s voice and Hagen flushed. He had deliberately not mentioned it... <<

This tells me that Vito didn't completely trusted Tom. It was Tom's job to get all neccessary info about Sollozzo. Obviously, Vito hired someone else to cross-check.
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About Michael's jealousy: Tom an Sonny were much closer in age. Sometimes it's difficult for a younger brother to get as close to the older one as he gets with friends and vice versa.

Vito's reference to Sollozzo's involvemnent with prostitution was probably due to the fact that Vito was well-known to be straightlaced about sex. The novel states that Tom had not mentioned it because it had nothing to do with business. So, I don't think it was a matter of trust. The derision in Vito's voice may very well ahve been because he loathed prostitution.

That was Vito's habit.....to go over things many times. As an old man he tells Michael to remember to have the "telephone man" come to sweep the place for bugs, and Michael says he already tok care of it. Vito then remembers this and acknowledges that he had forgotten he already reminded Mike to do this. That doesn't show a lack of trust in Michael, it is a typical Vito characteristic, and I think that's what wa going on when he reminded Tom about Sollozzo's prostitution links.