Music Soothes the Savage Beast

I have written about Elana's screaming at night.  I finally think I found out how to calm her down.  I started play children's lullaby's through Spotify.  The first time, she screamed and then calmed down.  Every time the song would change, she would get upset.  Lately, she seems to be happy when I play it for her.  I'm glad I found something.  The only alternative I could think of was noise cancelling headphones.