How do I get power of attorney over my sister that has Aids and is suffering from some form of aids related dementia. She is refusing care while hospitalized and wants to go home and die.

Power of attorney merely allows you to sign for her if she is not present or can not personally sign. Power of attorney does not allow you to sign or agree with anything that she does not want. So even with power of attorney she can still refuse medical treatment.

You are wanting guardianship where you can order her medical care.

You will have to file in court, with medical evidence she is no longer able to make her own choices.

You have one of 2 choices.

1) you allow the state to take over her care through a case worker and then apply for guardianship.

2) you apply for it before the courts and claim her unfit and be able to prove to the courts satisfaction that she is unfit and can not do for herself.

The problem in having her sign anything is that the excuse your using is that she is unfit in the first place so there is no room left for her to give it away. If the dementia is severe then it has to be taken by the courts.