Can Xanax Be Taken For Treatment Of Anxiety In An Elderly Woman?

Is it safe for my 93 yr old mother to take xanax (0.25mg) on a nightly basis for sleep? She has always been prone to anxiety. As her daughter, I am encouraging her to reduce her use to 1/2 tab at night, yet she states she is sleeping even with that lesser dose except she wakes with diarrhea and is afraid she won t make it to the bathroom. She seems to be more unsteady, anxious and weak in the past two weeks. She is jittery when supported in a transfer. She is afraid of having incontinent diarrhea and has been taking Imodium but then takes a stool softener within 24 hours because she is afraid of not having a BM. She has been told by her doctor to stop both to normalize. Currently she is less able to walk very far (using her walker) and is quite shaky. Could this be a side effect of the xanax for an elderly person (93y/o)?