Legal Question in Family Law in Kansas

If the poa was just for selection of medical care and to handle her finances, then she probably does not have the authority to prevent family members from visiting. If it is a general poa, she might. If she is the one paying the nursing home bill, they may honor her wishes to keep out certain people. If your mother can voice her wishes, then you might write to her ans explain that if she wants you to visit her, she'll have to tell the nursing home that.

Good luck