The title characters in Franny and Zooey are a brother and sister who, as the result of their shared upbringing and education, are dealing with the same problems in rather similar ways. Family is somewhat isolating in the sense that both Franny and Zooey Glass can only relate to their siblings, not to anyone outside the Glass family. While family is the source of many problems (Zooey blames his older brothers for his anti-social nature), it is also the solution (Franny can only get help through her spiritual crisis by coming home to speak with her brothers).
Seymour's death has affected Bessie more than any of her children.
Seymour's death has affected Zooey more than Buddy or Franny.