By July of 1973, Don and his younger brother Phil Everly were barely talking. They would stay at different hotels, take separate cars to the gigs and even use separate dressing rooms. They'd fight like cats and dogs until the curtains were pulled apart and the show started. They were making good money as the Everly Brothers and, like Siamese Brothers, seemed to be stuck with each other for life.
Then on July 13, 1973 at Knott's Berry Farm in Buena Park, California, Don walked on stage after knocking back a few margaritas. He slurred the words. He sang the wrong words. He sang flat. At the end of the show, as Don took his bow, Phil smashed his guitar, walked off the stage and announced "I'll never get on a stage with that man again."
They only met once over the next decade : to bury their father.