I've read of several lawsuits over that issue when grandparents bought into a 55+ community never intending to raise grandchildren but then gained custody when for example a single mom dies unexpectedly, or both parents are killed or get addicted to drugs. What, they're supposed to move out now?
OTOH, they did sign the covenants, and lots of people buy into those communities because they don't want to deal with the neighbor's noisy and ill-bred little brats. (Present company excluded, of course.
) I never did find out what the resolution in those cases was.
Rock, meet Hard Place.