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Kenny Rogers admits it's not often that he'll just come up with a song out of the blue.  The country star says more typically something happens that sparks an idea. 

Kenny says he shared the line with songwriter Don Schlitz - who penned Rogers' signature hit, "The Gambler" - and the next day Don gave him the song "You Can't Make Old Friends." 

Rogers adds that he knew right away it was the "perfect" song for him to record with Parton. 

"You Can't Make Old Friends" is also the title track to Kenny's latest album, which is in stores now.