Filmmaker Rory Kennedy, 43, the youngest of the 11 children of slain US Senator Robert F Kennedy and his wife, Ethel, persuaded her mother to give her first extended interview in more than 20 years for a documentary, the first film about the Kennedys to come from within the family.
Even so, it was not easy. "Why should I have to answer all these questions?" Ethel Kennedy, 84, asks her daughter in the film. "All this introspection. I hate it."
Ethel brings together rarely seen home video, photos, television footage and anecdotes from several of the children of Ethel and Robert Kennedy.
It traces the couple's early courtship, life at home filled with dogs, horses and even a pet seal, and the political careers of President John F Kennedy and Robert. Both were killed by assassins.
"I didn't really want to do it mostly for personal reasons.
"I didn't want to ask my mother and my siblings to go through some of the difficult moments," Rory Kennedy said but added she was persuaded by friends at HBO to do the film, and by the agreement of her mother and siblings.