I believe with a healthcare power of attorney you could make medical decisions for your step-son. I do think this is something Mom and Dad should agree to grant to you. Since they have joint legal custody there needs to be an agreement between them regarding major decisions related to their child's medical care. I think authorizing someone else to make medical decisions for a child is a major decision. You should contact an attorney for assistance.
Travis A. Van Winkle The Law Office of Travis Van Winkle, LLC does not intend for this response to be construed as legal advice. Instead, it is intended as general information. You should consult with a lawyer for legal guidance regarding the specifics of your case.
Lets first differentiate between medical check-ups versus emergencies; I doubt, in all honesty, anybody would have an issue with a step-parent taking the child to the emergency room if that need arose.
But, step-parents have very little rights in custody, and certainly none that would allow them to make legal decisions.
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