You won't.

( There is a fierceness in that, a fierceness that she hasn't had since before she died, wrapping her arms tighter around Sarah. )

I don't care if I have to tear apart the bloody walls between worlds myself, Saroula. You aren't going to die on that beach. I won't let you. You are going to live, and you're going to have a long, happy life with Kira and your family. I don't care what I have to do to make sure that happens. You will live and you'll be happy.