From Karen:

Has anybody else noticed that the song “In Dreams”, which is a recurring theme throughout the LOTR score, sounds familiar? It drove me crazy for a few hours until I figured out where I’d heard it before. The tune is almost identical to an old familiar hymn that most of us learned in childhood. The first two measures are exactly identical, and the next two are the same only a third higher than the hymn tune. I’m sure that this was entirely unintentional on Walsh’s and Shore’s part. It’s an easy thing to happen when you’re writing music. And it didn’t spoil the score for me; on the contrary it added a depth and connection with my childhood. I don’t want to spoil it for anybody, so I’ll just say that the hymn was written by Maltbie Babcock in 1901.