I have often wondered how two people could have been raised in the same household for so many years and still have one become so self-centered that she can assume to change a house that isn't hers every time she visits. This is what my sister does in my house each time she visits, which is quite frequently, since this is where our mother lives as well. Granted, we both grew up in this house, but she does not live here any more and my mother will say nothing to her and if I say something, mom gets upset. Since mom is elderly and not in the best of health, I keep my mouth shut for the better part of sanity after my sister leaves from her visit. I am a caregiver for my mom and she feels that she is the most knowledgeable person for this family. So she has a PHd. So she is in gerontology. So what. I LIVE HERE!!!!!!! I PUT UP WITH MY MOM'S IDIOCENCRACIES DAILY.
I just wish she would stop deciding that "this" doesn't belong here and "that" can't be there. She moves things and changes their position each visit so that sometimes we don't even know where she has placed them. It may take a week before we find what she has moved and then to find where she has moved it to may take even longer.
All I know is that if this continues after my mother's death, then she is very politely but very strongly going to be told that this is not your house and stop thinking that it is.