Kennedys, especially Robert were also tight with Senator Joe McCarthy, interestingly enough. Research it.
As to the article, I'm not that sure. I always thought the RFK assassination was pretty open-and-shut.
From the article: How do you explain this?
"The only way to explain this that there was a second gunman in a position behind Kennedy, but the prosecution never proved that Sirhan was behind Kennedy or was able to shoot him point blank," says eyewitness Paul Schrade.