Did you know that Sean Hannity and Bill O’Reilly of the FOX NEWS can't stand each other? If so why or why not?

"Ailes also faced internal resistance to Beck’s rise. Sean Hannity complained to Bill Shine about Beck. And it didn’t help matters that O’Reilly, who had become friends with Beck and can’t stand Hannity, scheduled Beck as a regular guest, a move that only annoyed Hannity further"