Barbara is Billy's daughter. In 1968, when Billy writes his letters about Tralfamadore to the local newspaper, she is only 21 and her mother has just died of carbon monoxide poisoning. The loss of her mother, Billy's very public alien abduction stories, and her sudden responsibility (along with her husband) for all of Billy's businesses turns Barbara into, in the words of the narrator, a "bitchy flibbertigibbet" (2.9.3). (Ouch.) She really is worried about Billy, but she's also incredibly disrespectful—she insists on taking over his life, making him even more powerless than he has been throughout the rest of the novel.