At this point, I don't believe Tori was specifically targeted.
I think that in a town this small people are bound to know each other, whether just in passing, buying drugs, from the grocery store, whatever. I think that a little girl would have died that day (or soon after) even if Tori hadn't unfortunately walked home alone that day...it would have been another little girl. Even if they had to grab one off the street.
I don't think TM buying pills from TLM's mother had any part of it and I don't think the girl MR dated, who had a daughter who played with Tori, had anything to do with it. I think they just waited for an opportunity, and Tori just happened to be walking alone that day. It looks like Tori was always with someone walking and that day just happened to be unusual and fit it with these



's plans.