Answer:  "Attaboy, Clarence." 
 In the final scene, George is holding Zuzu as the crowd sings "Auld Lang Syne." The are standing by the Christmas tree when a bell rings.
Zuzu:  Look, Daddy.  Teacher says, every time a bell rings, an angel gets his wings.
George:  That's right, that's right. (Pause) Attaboy, Clarence!
Zuzu was played by Karolyn Grimes, who also appeared in the popular Christmas movie, "The Bishop's Wife".