Your want a spoiler or no
Hmm.. yah explain
Yes please
SPOILER
STILL SPOILER
She don't. Keira is indeed the real daughter with the ability and the blonde girl "stole them" the way the sister of a previous spirit user did. Blondy could borrow her ability because her body is blood related to Keira. The prophecy is saying that Keira is the only real daughter however because Blondy soul his not her "real" soul. So the real blondy is dead and the ebeil Blondy is just using her body as a puppet to target and kill Keira.
Wait I need to refresh my memories but I'm too lazy to reread this. Why that ugly blonde have the power of spirits eventhough keira is the real daughter?