The POA papers my sister has don't look legit. Does there have to be a date to be legal?

Whether the POA is drawn up by an attorney or is just a purchased or downloaded form, it needs to be signed by your mom and then the attorney or a notary. The person who signed the form to make it legal also dates his or her signature. A notary will generally use a seal, as well.
Take care,
Carol

Red flags...hospital should not release info given a phony document, they should be afraid of the HIPAA violation. If mom is still competent to do a POA, you need a real one, and sister's motivation for presenting a fake one is certainly unclear. Is it possible she just does not know what's actually needed, or why it's important? If mom is not competent, and the POA is either fake or not set up to be "durable" a guardianship may be needed - especially if you think any monkey business is going on here. Granted, sometimes things are done informally, e.g. If one of you is with her when the doctor or nurse sees them, they will often go ahead and answer questions, etc. if Mom does not object, but good luck getting a list of meds or anything else out of the records. You can be rep payee with or without POA, but buying or selling assets requires one to be legit. I would think the safest thing to do would be to get an estate planner to look this over and/or consult with an eldercare attorney. Collect a copy of that POA and keep it, as protection against it getting altered as you start looking into it. BTW there are two separate POAs to consider, one for financial and one for health care, usually including advance directives too. Hopefully your looking into this will end up being helpful to all three of you and sister is not up to anything that's not legit...