I looked after my Mama for the last five years of her life, during which time her physical and mental health deteriorated. Dementia crept in and I did as advised here, so when she thought I was her younger sister, I played along quite happily. However, what I would say Olene is that you probably do not fully realise how relieved and, probably, grateful your sister must feel about getting a break. However much you love them, caring for an elderly parent is exhausting and emotionally draining as, unlike when caring for children, you know that your loved one is only going to get worse and, eventually, die. Think of this as an act of sisterly love and kindness. I wish that my sister had been loving enough to help me and our mother. I hope all goes well and the experience is not too trying.