How do I relinquish a POA?
We cannot give legal advice. The following is not a substitute for the advice of a local attorney. But we hope the information will be useful.
If I understand you, you want to relinquish your power of attorney for your mother's medical decisions, and perhaps have that power taken over by the sibling who has POA for her financial matters. You should REVOKE your POA, then have your mother sign a new POA for medical decisions to your sibling.
You can purchase these two forms from us:
A new POA for health care decisions