This story is a sequel to Bride of Discord

Discord and Fluttershy are blessed with a daughter named Screwball, who is gifted with incredible power that attracts the attention of the Queen of the Changelings...as well as her son.
When disaster strikes that tears Screwball's family apart, it is up to her to bring it together again.

New cover art by floppy-fluttercord

It has been weeks since the defeat of the Dazzlings, and Sunset Shimmer's friendships have only gotten stronger. Whilst finally relaxing in the times of peace, Sunset discovers an old enemy: Sonata Dusk. Strangely alone and apparently homeless, Sonata's luck seems to be at its all time low.
Seeing a little of herself in the former siren, Sunset embarks on a mission to help Sonata find friendship.

(For anyone who liked the old cover art, here's a side-by-side comparison of the old and new: http://daniel-gleebits.deviantart.com/art/Go-Compare-Twiddles-moustache-581352606 )

TV Tropes page: Feel free to add whatever tropes you find
http://tvtropes.org/pmwiki/pmwiki.php/Fanfic/TheEveningSonata