Who is Enid Lamber from The Corrections and what is their importance?

Enid Lambert is the wife of Alfred and they live in their house in St. Jude. She is the mother of three grown children. Chip is a writer who lives in Manhattan. Denise is an executive chef in a ritzy Philadelphia restaurant and Gary is a successful banker with three children. Enid is constantly complaining about Alfred just sitting around and feels that if other people who have health problems can be physically active, so can Alfred. She keeps nagging him which doesn't help the situation, even though she means well. Enid and Alfred always spend Christmas at Gary's in Philadelphia. This year she wants the entire family to come to St. Jude for one last Christmas and tells Denise to talk to Chip and Gary about it.