The girl is singing a very old griffin lullaby called "My Little Hero" to Spike (Yeah, My Little Hero: [something] is Magic. I realised that after I gave it that name, but I don't want to change it since it fits the image so well.) The lullaby would be in tone of Zenith by David Larsen ( [link] ) which ispired whole story.She sings this one to him, because he almost died in the mountains trying to save his friend, thus he is a little hero to her.Some sketches and description of the story: [link] Design of Spike © My Little Pony © HASBROEdit: Why are Brony musicians so amazingly talented? If do you want to hear something incredible, listen to this: [link] And I recommend you to check ~ WoodyJack 's whole channel. You won't regret it. At least I didn't.