True--I had forgotten about that. But the boggart was a one-time thing and the kappa incident never really got brought up again aside from it, at least not explicitly. However, it does play a significant role in my own personal theory of Alex as you know (that she hates herself); it's the first time, at least that we know of, that someone almost died because of her.

(Well I suppose you could argue Hecate became a vegetable as a result of worrying about her, at least if you buy Abraham's story, but that's really stretching things and anyway it couldn't impact Alex's personality until Book 4 when she learned it.)

There's also, and I just thought of this, the possibility that even as a young child Alex blamed herself for Claudia not becoming a doctor. Come to think of it, did we ever learn why Claudia didn't become a doctor? I assume she ended up dropping out of medical school, but I don't think it was ever actually stated...