MO - Our 17 year old son got a ride from his 1/2 sister when he was at work one night, unbeknownst to us. She lives 1 1/2 hours away. He is refusing to come back home. He is not emancipated. Since he is not 18, can we legally "force" him to come back home? We are very concerned that he will not complete his last year of school and that he will just do whatever he wants since he has no parental supervision where he is.