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. 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.