User blog comment:Xilinoc/Ch. 633 - FRIEND 3/@comment-8669536-20150702091412/@comment-8669536-20150702092447

Well, the normal theory regarding the Kurosaki children is that they were unaffected because their Quincy powers were completely dormant, and at the moment I can't think of any better theory. Uryū however is an entirely unexplained abnormality, so I'm thinking he is Jugo2, with his Juju-powers being entirely unawakened except for his Auswählen-immunity. I'm thinking the reason he can form Heilig Pfeil and so on is because there weren't really many other Quincy around to leech on him.