Would their dental work show that they lived somewhere else (other than the US)? The kids might be too young to have any, but I know on some other cases they can tell WHERE they lived (based on tooth formation? minerals in the water?)
As far as schools/churches noticing them gone...my mom worked in a school for 20 plus years and every year there would be kids that just wouldn't show up to school and with no notice. Everyone figured that the family moved and didn't notify them, or they were migrant workers of some sort. No effort is made to contact them other than perhaps calling the phone # listed in their forms. The phone numbers for ALL the enrolled kids were wrong more than half the time because parents forget to update them. Anyway, what I am trying to say is that it is easy for a family to disappear-- unless they have close friends or other family members watching out for them. I have left churches more than once and no one ever called me to check and make sure I was around.
Also, remember that case in AZ where the perp took some of her kids and her "adopted" kid camping? The "adopted" child was killed. That child's mother had just kinda given that poor baby to her friend to raise because she was a druggie. So we could have a case like that. (Sorry I don't remember the child's name)
There are a lot of transient families out there- not homeless but living a month here, a month there, a week in a hotel room and a week in a friend's basement. Sometimes they have a phone, sometimes they don't...and I think the people they know don't expect to have regular contact with them. And after enough time goes by they just shrug and figure they moved on to a better life somewhere with a new boyfriend or whatever.
