Most mafia wives nag and thats what Kay did always asking questions, really annoying. I believe DIane Keaton played the part well. Especially when she tells Michael about the abortion.

"Well you just do what I tell you to do! Goddamn it! If I had a wartime consiglieri -- a
Sicilian -- I wouldn't be in this shape! Pop had Genco -- look what I got." - Sonny Corleone