(CNN) -- "He's so good," Phil Everly said. We were sitting in a corner booth at a rural cafeteria in Muhlenberg County, Kentucky. Phil was talking about his older brother, Don. Having spent time with the Everly Brothers on the rock-and-roll road over the years, I had long noticed something: Whenever they were performing, Phil fastened his eyes right on Don's. As they were creating their heartbreaking harmonies, he seldom looked away. I didn't want to ask him about that in front of his brother, but, with just the two of us there, I did. "I have to pay attention every second with my harmonies," Phil said. "It's like playing tennis with someone who is really great. You can't let your mind wander for even a microsecond, or you'll be left behind."
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Bob Greene: The Everly Brothers had a talent that was extraordinary
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In five years, they had 25 hits in the Top 40 charts, he writes
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Despite frictions between Phil and Don Everly, they were masters at working together, Greene says
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Greene: Paul McCartney and John Lennon used to pretend that they were the Everly Brothers
The fact that he and @placeholder went through long periods of estrangements and silence is not a secret, but the silences ended each time a show began.
"I had this haunted feeling all my life," Don said to me one day in @placeholder.