I think at that point, Michael was talking more about himself than Fredo--about how hard it was for Michael to be Vito's son. If so, it'd be a rare crack in that cold facade.
Ntra la porta tua lu sangu � sparsu, E nun me mporta si ce muoru accisu... E s'iddu muoru e vaju mparadisu Si nun ce truovo a ttia, mancu ce trasu.