User blog comment:FairyRaven/Fairy Tail Chapter 368: The Third Seal, Review and Commentary/@comment-4829046-20140125070131

I'm sticking to my theories that Silver is either an alternate Gray or Gray and Silver are both demons from a particular chapter of the Book. If you don't know what I'm talking about, then ignore this, I myself don't really know how to explain it, but if it does happen in some similar way, then I am totally claiming it. >:)

Not that there aren't other good theories that aren't bullshit like Future Gray >_> but these are my own theories.