The idea of the Scent and the general AU are great, and your flow was fairly good, but I think Sophie's power is a bit too unrealistic. Prehaps if she were only immune to the Scent spell, and similar tracking spells, it could be believable. But to be immune to all spells is a bit of a stretch. Keep on writing though, you show a lot of promise.
I'm glad that you gave the trio more people to back them up. And Sophie sounds like the kind of girl who's willing to help them. It's always interesting to add your own ideas and think, "what if?" That's what the alternate universe is for, of course. Great job!!!
I like this chapter, and the concept of the Scent. Although it is similar to the Trace, something about the word "scent" and how you described the Death Eaters being so persistent in placing it on newborn babies made it all that more sinister, and therefore quite original, in my opinion. However, if you reread DH, then why did Hermione say Voldemort twice while they were in the camp? Because, if you'll remember, that was what got them captured in the book, because a charm had been placed on the name. I don't know, I just thought that canon-based or not, it's still an important part of the book and really shouldn't be disregarded. That's just me being nit-picky, though, because I really enjoyed this chapter! (sorry I wrote you a novel, here...I just had a lot on my mind)
Author's Response: Thank you so much for the review! You're right about Hermione and the taboo on Voldemort's name. I have not realized that before. When I was writing it, I was thinking mostly of a completely alternate scenario, and didn't pay much attention to details of canon. Thanks for pointing it out, and for all of your comments, I really appreciate it!