I think this quote is the best of all the three parts.

FREDO you're nothing to me now you're not a brother, you're not a friend, I don't want to know you or what you do -- I don't want to see you at the hotels -- I don't want you near my house -- when you see our mother I want to know a day in advance, so I won't be there -- you understand.

I got two brothers my self and i think it will be very tough to speak to you're own brother that way.