Country singer Charlie Louvin, who died earlier today, was on Fresh Air in 1996, where he explained that he found it difficult to sing without his brother providing harmony on his tracks: "I’d always believed that any song worth singing is worth putting harmony on. And, of course, I had gotten used to that for the 23 years that my brother and I had worked together. And even today … when it comes time for the harmonies to come in, I will move to my left because my brother and I always used to use one microphone, and so you had to share the mic. And, even today, I will move over to the left to give the harmony room, knowing in my mind that there’s no harmony standing on my right. But it’s just old habits are hard to break."