In the night following Nightmare moon's return, Celestia senses that her sister is in emotional pain, being the good older sister that she is, she decides to go see her.
*note* I know it's terrible, it was written entirely on a touchscreen. As well, it was written as I had it come in my head, with zero editing, between school, and other commitments, I just didn't have time. It may see an edit in summer, but that's a big MAYBE.
I just wanted to make sure people knew i wasn't dead.