It is a strange statement because out of all the child killers I know of well enough to have seen a picture none of them were ugly toothless or deformed. I would say normal looking is the norm and ugly/deformed on the inside where (sadly) no one can see. I may be wrong though-I really haven't taken a survey of all child killers charged in a year or anything.
I also completely believe no one in the neighborhood saw anything. I live in a similar neighborhood (not location-wise, but from what I can tell a similar make-up) and after 8 everything is dead. Most people are shopping or at work or on a bus (students). It could very likely be the same in her neighborhood-very still at that time except for the stray kid, person, and unfortunately predator