Yup,not being married at the moment...and having no kids..I named my sister as my heath care proxy,my POA and the executor (executrix?) of my estate. My lawyer told me that the documents I signed give her the most authority allowed in every scenario (coma,respirator,emergency surgery,mental incompetence,etc,etc) allowed under state law.
Well you have to trust your sister. I wouldn’t trust either of mine.