I went and got written power of attorney with my parents and had it signed and notarized by the bank. She went above me and had her husband made power of attorney. They have dementia and now reside in separate facilities because my sister doesn't want them together. She had also made it to where my daughter, my husband and myself can not visit either. She claims we are a threat to their well being which is absolutely false. This is a childish vendetta and I need to know how she accomplished this and what I can do to fix it.