UnMarried Parents Beware

especially since puritanism came from... New England....

my question is, if all the kids are related to one or the other (and possibly both) parents involved, how would such a law apply?
I know they are intended to keep hippy communes, gang houses and drug houses away, but this is putting the township at great risk.
When the lawsuits are done, the couple will OWN a home and not be under the council rentals.
(the home/apt is owned by the city, right?)