I share caring with my sister and 90 year old father. I sleep in mums room twice per week to give dad a break. Last week she didn't recognise me for the first time and went berserk, barging into dad's room, demanding I was sent away, and calling me awful names sac. At one point she attacked me. It was very distressing. I am due to be there agin tomorrow but have no idea how to handle this situation if it occurs again.