What Difference Will It Make?

In the Hall of Prophecies if you walk to the 51st aisle on the second to top row, fifth to your left facing, you will see a rather dusty prophecy ball. Issued by yet again Trelawny from the first of August. This one is for no other than Shadow Potter.
Potter? How can this be? You may be thinking of her as aunt or something along those line from her father’s side, but this is some information. Let’s see if you can guess.
1.She has poor eyesight
2.She was branded as Harry in a different place and in a different way, but by the same person, at the same time.
3.Her godfather is Severus Snape
4.Her father is James Potter
5.Her mother is Lily Potter
6.She was born at around the same time (take or give a few minutes) as Harry
7.She was born in the same place as Harry
8.Same place, same time, same mother.....ring a bell?
Honestly, are you that clueless? In case you haven’t gotten it yet....
She is the twin sister of Harry Potter

I will add a sequel so that Shadow Potter doesn't wallow in misery. I will also add that this story has a twist. Hope you enjoy!

I do not own any of the J.K Rowling characters or set, but I do own Shadow, Amaya, and some random people that'll show up. Don't sue!

Rated R for abuse, rape, and heavy language in later chapters. If you think that the rating should be changed, message me.