Reparenting the child classes causes a crash too. I guess I’m switching to C++? Not sure what other options there are that don’t include “create everything from scratch again”.
Edit: Reparenting the last child, then going backwards, worked fine. Made the blueprints all bad though, as the functions no longer exist.
Edit 2: Managed to crash again, this time by compiling a completely unrelated Blueprint. Perhaps I wasn’t made to use Blueprint. >_>