Why does my 100-year-old mother insist on taking a shower when she had already done so earlier in the day?

A few months before my mother turned 100 years old in August 2011, she would often tell her caregiver that she had not yet taken a shower, even if she had only done so a few hours before, or sometimes towards the late hours of the afternoon. And this happens now almost on a daily basis. She is assisted by two caregivers when taking a shower. My sister, with whom my mother lives, has an 82-year-old husband afflicted with Alzheimer's and Parkinson's diseases. My sister and the caregiver have even resorted to taking a phone video of my mother in the bathing process, something that I do not agree with because I feel that it is a violation of my mother's remaining dignity and privacy. My sister claims it is a way of proving to my mother that she actually took a shower on a particular day. My mother becomes frustrated, angry and irked when she is not allowed to take another shower during the day. She cries; she questions my sister and the caregiver about why they won't allow her to take a shower when she hasn't showered in the last two weeks, few days, or that day ... it varies. Friday afternoon last week, I received a call from the caregiver telling me that my mother again wanted to take a shower but was prevailed upon by my sister from doing so. Added to that, my sister locked the door to the bathroom so that my mother could not enter. My mother asked the caregiver to call me up ... on the phone, in between sobs, she told me to pick her up from my sister's house ... she said she could no longer stand the way she was being treated ... and that she wanted to stay with me ... could I please pick her up. I was sick that day, but I got up from bed, dressed up and went to my mother. In my sister's living room, I saw that there was a bag packed by the caregiver containing some of my mother's clothes and other essentials. My mother said that she would like to be removed from my sister's house ... that she would stay with me only for a limited time, until she could fly back to our country and stay there permanently with her caregiver ... that my sister was getting to be too much and that she no longer liked the tone of my sister when talking to her ... my mother was crying ... and it had been a long time since I saw my mother in that state. My sister's words, tone and manner of delivery seem to have weighed heavily when received by my mother. My sister was watching soap in my mother's living area (near the living room). Then my mother asked the caregiver to call my second older sister so that she could say her goodbye (my second sister lives in an apartment two buildings away from where my mother stays). When second sister arrived, she talked to my mother and explained that my eldest sister had already reached her limit--taking care of a sick husband who is more often than not in bed, eating meals and watching tv with closed eyes, incontinent and sometimes even excretes all over the bathroom, etc., and coping with an elderly mother who insists on taking a shower even if told that she already had one during the day. Added to that, second sister told my mother that she was again having one of her tantrums and behaved in a somewhat spoiled way, whenever my mother did not get what she wanted. She toldl my mother emphatically that mom was getting old, unable to think clearly, and that she should listen to what the people around her are telling her. The tone of my sister was rather harsh, definitely not compassionate and caring. I felt badly for my mother who suddenly acknowledged that it was all her fault and her reaction was to leave. What I saw was a deeply hurt 100-year-old woman, my mother, who could not express herself as easily as she could maybe 2 years back, not as mentally alert as she was in her younger years, and could not think very well owing to the non-stop homily of second sister. I could sense that my mother was under some sort of pressure. I called the attention of second sister and told her to give my mother a chance to think and talk ... impatience is one characteristic of second sister. I told my older sister that my mother seemed frustrated that she could not enter the bathroom as it was locked and that there was a better way of handling the situation, perhaps. The caregiver was ordered by my sister to call me up the next time my mother goes into a similar tantrum again. Much as I didn't want to, I had to leave my mother in my older sister's house with a fervent resolve to consult a geriatric physician or resource to seek an explanation as to the behaviour of my mother regarding the desire to shower frequently during the day ... and to obtain tips on how to handle the situation in a more compassionate and loving manner ... because when we were young and helpless, insistent and belligerent as children, our mother, most definitely, must have handled all of us with care, patience, gentleness, affection, tenderness and motherly love. I believe,it is now time to handle our mother in the same loving way.