I was just watching an episode of The Shield and the cops go into the room of a woman who has a baby. It’s a really brief scene, but in the background is playing “baby music.” I can’t really convey what “baby music” sounds like, though. Well, I can try to describe it. It’s all in a major key; it sounds like it’s played on bells, chimes or xylophones or something; and it’s vaguely similar to the kind of music that is played on carousels. Or the kind of music that a music box makes. For instance, the “Rugrats” theme song, if anyone remembers that show from Nickelodeon.
Why is this kind of music associated with babies? When did it first originate?
Wild-ass guess: The music box comparison may be a key here. If a baby is grouchy and finds the sound of music soothing, a music box would have been the most easily-available option (aside from the mother humming/singing) for most families for a very long time, until more modern conveniences were available. This would be especially useful if the baby was having a lot of trouble sleeping soundly, and needed frequent encouragement to go back to sleep - a music box might be an acceptable stand-in for mommy’s humming, giving her a bit of a break.
Sung lullabyes are cheery and soft, not too energetic, and repetitive to encourage sleep, and I know that many baby items (before cheap, small electronic components) were made available that played lullabyes on music boxes. It’s probably sunk in to our society as a ‘shorthand’ for ‘baby’.