premise: Singers Bryan Ferry and Joss Stone, plus US rapper Pharrell Williams will also appear as will further acts yet to be announced.
  Diana's love of musicals and dancing will also be recognised with a performance by the English National Ballet while composer Andrew Lloyd Webber will put on a medley of songs from his stage shows.
  Harry said he and his brother would likely appear at the start.
  Royals and Diana's relatives will attend the memorial service in a rare show of unity.
  "The service is going to include both sides of the family, our mother's side and our father's side -- everyone getting together," Harry said.
   What could be achieved when Royals and Diana's relatives attend together?
hypothesis: a rare show of unity