Polly Klaas ' father joins search for teen . Hailey Dunn , 13 , has been missing since December . Her mother says she was last seen at a friend's house in the small town of Gillette, Wyoming on Friday. Both mother , boyfriend have failed polygraph tests .
Polly Klaas ' father joins search for teen . Hailey Dunn , 13 , has been missing since December . Her mother 's boyfriend is the focus of the investigation . Both mother , boyfriend have failed polygraph tests .