Saw that one little boy in Riverwood once just standing in the middle of the road at 3AM just staring off into space.
Freaked me out, haha.
In one of my games (I play 3 characters), he stands near the Inn at the intersection and looks up - weird thing is, he's been standing there for almost a month now. He's there 24/7, doesn't go home, nothing.
And a little girl stands just at the end of the town where some soldiers have their "bed" laying on the ground near a fire. She's been there just as long.
You can talk to them, but nothing else. They won't move.