it is unusual. perhaps the boy who's age is 20 years, do not do any work, i mean to say jobless. as a neighbour you might be feeling disturbed.
actually, for legal action you do not have any lucas standi. go 3/4/5 gentelman of her neighbouring area, convince her that such type of treatment is bad not only for her son, but also for other boys and it is polluting the social atmosphear.