Legal Question in Juvenile Dependency in Washington

You do not need to keep him on your auto insurance policy. However, I suspect you are really asking if you are liable for damages he causes with his car because he is living with you. This is an "agency" question. Make sure he isn't driving your car. Make sure he isn't running errands for you. Keeping him on your insurance may actually make you more liable. You should contact your insurance company.

As to his medical bills, that depends on the particulars of your health insurance. You'll need to review the fine print.

At your service,