My niece and I are both POA and MPOA for my sister. We think she is showing signs of dementia and we are wondering what the steps are to declare someone incompetent (in California). She is 83, has short term memory issues and repeats herself terribly.
If you need guardianship for placement then this will go through an elder law attorney who will file in court, and the court will rule based on her medical doctor's assessment, and etc. but the attorney will guide you through it. It will entail a court procedure.
Be very certain that you actually WANT guardianship; it is a massive undertaking mentally and emotionally and time wise. This will mean that whoever is appointed, you or your neice, will be filing all the papers, and paying all the bills and getting all the medicaid documentation, etc. If you do not wish to take this on then ask that the court appoint a fiduciary to manage money and continue to do the medical power of attorney or ask that there be a court appointed guardian. If the neice wishes to take it on perhaps you can help her with it. Good luck.