Clemenza telling Michael that they were all proud of everything he did during the war, including his father.
After Sonny's death at the tollbooth, Don Vito has Tom call the mortician Bonasera to repay the favor he owes. Bringing Sonny's body to funeral parlor, Vito begs for the favor:
Vito: I want you to use all your powers, and all your skills. I don't want his mother to see him this way. (he pulls away the sheet to reveal Sonny's bullet-riddled corpse. After a moment, Vito begins crying)Look how they massacred my boy...
Subverted in Part II, near the end when Mama Corleone passes away and Connie talks Michael into forgiving Fredo for his accidental betrayal. Michael comes out of hiding and hugs his grieving brother... only to coldly look up toward Al Neri, who nods quietly back to his Don. This is the Darker and Edgier sequel: Michael's not about to forgive anyone...
Michael and Sonny's last scene together before he goes off to kill Sollozzo and Sonny's promise to let Kay know when the time is right.
Vito saying to Michael "I never wanted this for you." combined with their prior discussion of Michael's 3-year old son reading the funny papers.
After Sonny's death, Hagen is shaken and goes to pour himself a drink. Don Vito walks in and Tom scrambles to the effect that he was about to waken him and let him know. Vito initially reproaches him, but later on, he embraces Tom.
"You've been a good son. You comfort me." Telling Hagen that he had acted properly in this terrible time.
The hospital scene in Part I. Vito is vulnerable and set up to be assassinated, and the only person there to help him is Michael. When he sees how much Michael cares for him and wants to protect him, he silently begins to tear up.
In Part II Grocer Abbandando is forced to give Vito's stockboy job to Don Fanucci's nephew. Abbandando is distraught when giving him the news but Vito tells him he understands and says he'll never forget how he took him in when he first arrived in New York when he was a boy. On the street Abbandando tries to give Vito a box of groceries for him and his family Vito politely refuses. When Vito comes home he places a pear he bought on the table, which is enough to make his wife happy. As they sit down to eat dinner Vito kisses her.
In the movie commentary, during the baptism scene, Francis remarks how blessed he was to have Sofia born to him at the time and pauses to note how cute she was.