Pray that they come to their sences and come back : D or call the cops
They can't without the parents permission because you are still their responsibility until you are an adult which is 18.
I believe that if they have a sturdy home you should be able to move out if you want as long as there is an adult in the home that you so happen to move in with.
Yes, it is perfectly legal.
the answer is yes she can, at 16 she would need ur concent. at 17 she can move out, with out parental concent.