For decades, rumors swirled that Patti LaBelle was feuding with Diana Ross. It all began after Cindy Birdsong left Patti's group, the Bluebelles, to sing with Diana and the Supremes. The controversy bubbled up again in 1985 when critics accused Patti of upstaging Diana during a performance at the Apollo. Watch as Patti reveals what really caused their famous rift. Plus, find out how Oprah's Legends Ball helped these two legends become friends.