What you can do is continue to have police bring the child home. Once you stop exercising that parental authority and allow some other person or the taxpayers to support your child, you open the door for that someone else or the taxpayers to seek reimbursement from you. You're the one legally responsible for providing for them, regardless of where they're actually residing. If you don't want him staying at grandma's, have grandma send him home. If she won't, or he won't come willingly, ask police to go GET him. Anyone enticing or allowing your child to stay with them against your wishes can also face criminal charges for interference with custody, or contributing to the delinquency of a minor, if you choose to go that route. Until he's 18, you can expect to be paying SOMEONE for his support, unless he's under your roof. So you can either pay for him, or chase him to keep him home.