For children, listening to music is like dreaming. Kids connect to the raw data feed and interface directly with the sound waves. I know this because I work in a school and I play music with kids almost every day. Also, I was a kid, once.
When we say "children's music" we generally think of music written FOR children. Children make their own music, and they do for reasons that meet developmental needs for expression, belonging, comfort, and complexity -- they sing to know.
My kids and I have been listening to Lisa Loeb's new children's album and book, Lisa Loeb's Silly Sing-Along: The Disappointing Pancake and Other Zany Songs, in the car for the last week and we have it fully memorized.