July 2017 marks 80 years since Amelia's plane disappeared on her historic round-the-world flight. Although there have been many theories as to what happened (including one circulated in Summer 2017) , no one actually knows for sure. Earhart's biggest fan and supporter, her sister Muriel, kept Amelia's spirit alive up until her own death. The documentary features interviews with Amelia's niece, Amy Kleppner.