Not much is known of Cathy except that she is older than Karen and she lives in Scarsdale. It is implied she and Stanley's second wife Karen are not in good terms as Karen calls her a "bitch" and Karen's maid Rosario describes her as "ugly". Karen also mentions that Cathy's body was ruined after giving birth to her children. After her divorce from Stanley, she married a plastic surgeon.
In one occasion, Olivia stays with Karen during the holidays because Cathy and Mason are in the hospital "sucking out part of his stomach and putting it into her flat fanny" with Cathy's new husband as the surgeon performing the operation.