Sounds like kids to me too. We came home from work one day years ago to find the back door open and obvious signs that someone had been going through the house. The only things missing were our jug of dimes (about $200.00 worth) and one of the kids Ninja Turtle movies. We had lots of guns and jewelry that had not been touched. We believe they were there when we got home and made a quick getaway out the back and into the woods.
A few days later, the police found the kids that did it and we got the movie and our jug back. Of course the dimes were gone.
That's really scary that they were in your house while you slept. Hope they catch whoever did it.