In this episode Blanche will do anything to keep the Mercedes! She says to Dorothy... I'll give you one of my sons... I have four children I've never had a Mercedes... which one do you want Biff, Doug, Skippy? If Blanche has four children how can she have 3 sons? We know she has 2 daughters which we've seen in other episodes... Rebecca and Janet.
Response: She said she has had four sons, not four children.