One thing I'd like to point out . Someone in the prior thread sort of mentioned this, but I don't know how to quote a closed thread. We can't KNOW that the Closs family had not had previous interaction with the perp. The two adults are dead, and cannot ever tell us whether they had, or had not, met or known of JP.
Extended family would not necessarily know all their acquaintances. How do I know this?? Because I know, and know of, MANY people who my brothers, sisters, aunts , uncles. grown children etc have no knowledge of whatsoever, and I actually come from a pretty tightly-knit family.
Adults have their own lives, work-place friends , hobby friends, etc etc who do not intersect with the lives of their entire family. I could probably name over 100 names right now of friends who I know through a hobby, that not one person in my family knows the name of, except for my spouse. (And in this case BOTH spouses are dead, and can shine no light on this. Which might be the EXACT reason they ARE dead. Maybe JP knew that one of them would realize the connection and blow the whole thing. It would explain why he didn't take her while Mom and Dad were at work, but instead waited to do something far more dangerous, which is risk being caught to take them "out".