Barbara "Babs" Pewterschmidt (née Hebrewberg) is Lois's mother and Carter Pewterschmidt's wife. She and Carter are both very wealthy, although she reveals that she grew up in more humble beginnings in Weekapaug, Rhode Island in "Absolutely Babulous" and only maintains a facade of class to please Carter.
Barbara was a Jewish holocaust survivor, as revealed in "Family Goy". When she married Carter, she had to conceal her religion, so that Carter could get into country clubs, which they both agree was "the right thing to do."
She once had an affair with Jackie Gleason, which traumatized their son, Patrick to the extent that he had to be institutionalized, as revealed in "The Fat Guy Strangler". Also, in "Peterotica", she left Carter when he was broke and went to Ted Turner, only to take his money and get rich again later on. She got back with Carter right after.
Both Carter and Barbara Pewterschmidt apparently have an addiction to sleeping pills and alcohol as noted in "The Fat Guy Strangler".