Who is Miss Kilsen from The Virgin Suicides and what is their importance?

Miss Kilsen is a social worker hired by the local high school several months after Cecilia's suicide. She acts as a counselor to the students. Little is revealed about her personality. Her real identification and credentials turned out to be false, and the narrators were unable to track her down for a possible interview. The Lisbon girls probably attended several meetings during which they confided to her. Sadly, all the records pertaining to these meeting were lost in a fire.