Sorrow of a Princess

Princess Celestia understands that she was only protecting the ponies of Equestria when she banished Nightmare Moon... But that doesn't mean she does not miss her sister terribly.

An amazing song that fits in perfectly here: [link]

Luna won't you cry for me?
I'm as lonely as I've ever been
I am forced back into the start
Is there any way to fix a broken heart?