People really need to brush up on Summer Knight...half this stuff is already dealt with in that book since we're introduced to all these new characters. Of course the Queen(s) can kill their own Knight, that was why Harry was investigating them in the first place. And he consulted on the matter with Bob. And the mantle 'snaps back' to the nearest Queen no matter who or what ends up killing the Knight. That's why Aurora was able to hide it the way she did.

And unless someone wants to argue that Aurora and Lily did the deed as a means of transferring the mantle to her before Aurora turned her to stone...I think it's a fair bet that either sex is NOT a requirement, just a fun bonus, or that only a Queen (not the Lady) can use that method.

That's the only explanation I can come up with, though Id like some nod to it one day. The only other option I can think of would be that the Queen of Winter is somehow immune, but CD certainly made that unlikely.

Is it not possible that she's 'immune' in so much that, if she's aware and on the ball, then like with the Gatekeeper's eye detecting Nemesis, it's next to impossible to N-fect a Fae Queen once you get into the Mab/Titania realm. It makes sense the Ladies can be vulnerable as the youngest, least experienced and powerful of the trio. The Queens might be able to be N-fected, but it's as unlikely to happen as anything (though some have, and will argue that Titania is probably vulnerable now in her emotional state, though I think it's overstated). And when you get to the Mothers, they are probably 'literally' incapable of being tainted.

'Mac has never done anything beyond a vanilla mortal' or something I think it was...