Stamp, I hope your trip went well. I'm very interested in this thread. Alot of interesting clues and circumstances going on that would make me question my neighbors also. Especially since they had a missing 6 yr old relative that hasn't been found. Are you sure they never had any resolution concerning the little girl in all this time?
There could have been and it just wasn't publicized. The family could have some answers or at least some type of truth as to what may have happened but since no one was prosecuted the public hasn't been kept informed.
What was her name, and her thread here at websleuths? Thanks so much in advance. I do appreciate your being aware and alert and bringing this here. Even if it turns out to be nothing, you still should have re-acted, as you had confirmation and affirmation from other neighbors too, including our husband. So you weren't the only one acting on suspicions and needing some answers. At least, something is not normal about an air compressor running constantly. These motors do run differently as you have pointed out.
I would do as an earlier poster suggested, go check myself when I knew they were gone. I also would try to get to know the wife just a insy bitsy more, I think you will get some peace of mind there, or some answers, or possibly have more questions. If you leave those encounters with more questions, then your probably on the right path of thinking. Local Law enforcement should be able to help you out concerning the latest updates and information concerning the six yr old. You aren't butting in, it's public information, by the way. Chase away the thoughts of your being nosy.
You have a right to inquire of law enforcement, they put this stuff out publically to use the public to get tips to solve cases. I just wouldn't accuse them, or cross the line, you do need more facts than you have right now before assuming there's more to this. Keep it here, for this is a safe haven to discuss it, and the neighbors won't be harmed in anyway. Because they are innocent so far.
Contacting law enforcement, the missing networks, mail man, electric company and your own personal observations are within the correct legal boundaries and shouldn't put them in any bad light.
Keep us updated, and I want to read the background details concerning her disappearance, so we need her name, or something to go on.
Take care, glad to hear your with your mom during her time of need, hope you enjoyed the time together, and can't wait to see you back here.
Sheila