Sound like it's time for tough love.
I'd give the house a clean sweep, every non working adult is on the sidewalk at 0700 activly looking for work. Yes, take the kids with you and when one goes into a business to seek employment the other is outside watching the kids. If your not working within a few weeks, don't expect to eat here. The shelter is just up the road or the next town over.

I don't take care of other peoples kids and them aren't his to care for. make that boy become a man and take responsibility. Your son needs to take charge....he wants to be a Hiway Patrolman and allows this stuff to go on in his house??? By God, I'd love to come over there and put things in order. I have no, zero, sympathy for lazy people.