Quote from Tommy in Green-Eyed Dick
Dick: Why am I so hostile to this Jeff person? He's never done anything to me. In fact, he seems like a perfectly tolerable twit. But for some reason, I hate him just because Dr. Albright likes him. Why? Tommy: It's called jealousy, Dick. It's what happens to Moose when Reggie flirts with Midge. If you'd read a little, you'd know something about this.