Things come to a head when Mrs. Wranglebury's mother comes unexpectedly to stay with them. Mr. Wranglebury borrowed money from his mother-in-law many years ago to start his business, and he is fearful that she may ask for it back.
The situation becomes tense when Mrs. Wranglebury's mother unexpectedly visits.  Mr. Wranglebury owes money to his wife's mother, a debt from years ago when he started his company. He fears she will ask for the money back.