"You have to keep her a certain distance from anybody who isn't fairy-guarded. The fairies won't or can't operate on things too far away from their people. Mine has a range of about a hundred yards, but they might vary. I don't know if you already have a prison setup that accommodates that. But the effects are persistent - my fairy isn't around right now and my dress and these magic shoes still exist, the coach is probably where I left it, she said they'd disappear at midnight but that was something she added because I complained. So just taking Kelsey away from my father will not fix him, although it might let the effect wear off by itself, if that's something it can natively do - in the same way that I could rip this dress."