if you set the boundaries on their behalf, they just learn dependence and not how to establish boundaries for themselves. let them get in trouble while they're kids. as soon as they move out or go off to college, they'll be wise not to get caught and to be responsible for themselves if they've had practice doing it already. otherwise, like several people I grew up with, they'll go off the rails and flunk out because they don't have any self discipline and the freedom they were denied their whole childhood was intoxicating