Strange???

Is this strange or am I just overprotective?

About three weeks ago two kids move in two doors down. A boy who is nine and a girl who is six, they have taken to spending HOURS at our house on the weekends. They are very good kids and have even taken out the trash for me and love to walk Lady ( they have a chocolate lab that had to go live with grandma when they moved). All this is OK and you may be wondering why I think this is strange.

The odd thing is that I have never even SEEN the parents (Josh met the Dad very briefly and thinks that he waved at the Mom once)! Now B and KK are wanting to go play in these people house and I will not let them. Of course the obvious answer is to get to know the parents but that is easier said than done.

Isn't it weird for these people to let their kids spend so much time in our house (even when Josh-to them just some strange man-is the only one here) when they don't even KNOW us!