Other mistake: In analogy to David's mishap with the champagne glasses old Mr. Larrabee crushes an olive jar when he sits down. However, in contrast to David he puts the jar into the front pocket of his pants, and olive jars don't break even if you sit on them (remember what he did to one when he tried to get the last olive out.). (01:46:55)
Factual error: When David talks to Linus about the consequences of calling off his engagement with Elizabeth he says that their father would take to the bottle and smoke six coronas. Throughout the movie the old Larrabee smokes one churchill after another, but not a single corona, which is significantly shorter than a churchill. (01:02:05)
Sabrina Fairchild: Goodnight, Mr. Larrabee. I'm sorry I can't stay to do the dishes.
Thomas Fairchild: I like to think of life as a limousine. Though we are all riding together, we must remember our places. There's a front seat and a back seat and a window in between.
Linus Larrabee: Fairchild, I never realised it before, but you're a terrible snob.
Thomas Fairchild: Yes, sir.
Question: Toward the end of the movie, when David walks into Linus' office and asks him if Miss McCardle has to be there. Doesn't Linus address her as Miss McCarthy?