We don't know if this was a planned or spontaneous sleepover, we don't know if NO was a frequent weekend overnight guest at his grandparent's house, we don't know if they locked all of the doors and windows before they went to sleep, we don't know if NO talked to other kids or adults while on the playground that day. It's entirely plausible that someone would ask him if he lived nearby and that he would tell them that he was staying with his grandparents for the night, even pointing out their house in the process, or that he would offer up the same information at the estate sale. Adults often make small talk with outgoing and adorable children and ask them questions about themselves. Children excitedly relay all details. So it's entirely plausible that perfect strangers knew he was spending the night.
You're right that taking the adults along pose quite a problem, but we do know one (or several) people were in medical distress. Perhaps this was more a hiding the bodies then taking them along?
You're right that taking the adults along pose quite a problem, but we do know one (or several) people were in medical distress. Perhaps this was more a hiding the bodies then taking them along?
It is rare for a child abduction to include adults. You are taking a whole lot of risk assuming the plans didn't change between the time you overheard the plans, and the actual sleepover. Given the age differences, there would be no reason to assume NO lived there if everyone knew it was the grandparent's estate sale. No forced entry suggests the perp was let in. If the perp knocked on the door, then they would know full well they would have do deal with the adults. It's not impossible... But unlikely that's what happened. Not that it's any great relief.