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If the 17 year old wants to stay away but the parents want the child returned, the 17 year old would have to get emancipated by a court. A child must be 18 to leave home without a parents permission; unless he or she is legally married.
A child over 17 cannot be picked up by juvenile probation because he/she is over 17 already. However, the parents can call the police to come bring the child home. The child is not emancipated by a court, cannot sign legal documents. Now if the parents do nothing, then there's no issue. But if the parents want the child home, the child would need to file for emancipation to prevent being home.
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