I supposeeee. Maybe you could have Mini Voldie kidnap Freya to some place who-knows-where and she has to figure out where his like 4 or 5 horcruxes are, and murder them. ALL before Mini Voldie DOES go all Voldie Kill-every-living-thing-that-bothers-me on her.
It's just that Seamus, for some reason, bothers me. I have no idea why. Well whatever. As for the whole Horcrux thing, I think you should come up with a whole new concept for Freya and Mini Voldie. Something somewhat like a Horcrux, but not.