Can you help me deal with a neighbours child?

We have more snow than normal this year, and at each side of our driveway we have some big snow piles.
Well this little boy from way down the street likes to dig snow forts and tunnels through these piles.
It is freaking Mrs Squeeky and I out because this little boy is unsupervised, and if these piles collapsed on him we would be liable, the mother seems to care less where the kid is and we never catch him at it.
How do we deal with this, the kid lives down at the end of the street and he is I would guess only about 5 or 6 years old.
He has made forts up by his house, but now I guess he wants to expand his territory.
How do we deal with this, do we have to get the cops involved I think they have better things to do.
I don’t want this kid getting hurt or worse on our property .