Quote 1
Sue: Research pays twenty-five dollars a week minus laundering the hair shirt. You've got to give up your life to go into it. (2.65)
While Kate and Ann both downplay their interest in economic comfort, Sue is very upfront about it. She openly encourages her husband to pursue money and resents anyone standing in the way of that.
Quote 2
Sue: I've got nothing against Joe. But if Chris wants people to put on the hair shirt let him take off his broadcloth. He's driving my husband crazy with that phony idealism of his, and I'm at the end of my rope on it! (2.89)
Ouch. What a thing to hear about your fiancée. On your engagement day, no less! Sue's accusations make Ann suspicious that Chris knows more about his father than he admits.
Quote 3
Sue: Chris makes people want to be better than it's possible to be. (2.67)
Sue is a resolute pragmatist. Chris inspires her husband to want to do research, when she just wants him to keep them comfortable at home by doing ore profitable work. She's hoping she can influence Ann to get Chris out of the picture so Jim will feel less conflicted.