What steps against harassment of my father by wife and son

First of all sir I'm a Hindu Brahmin and I'm going to tell each and everything that is going inside my family sorry this is not family. Doing a Ayurveda experiments on my dad body when I can see everything is going wrong on my dad health. I'll explain my dad is suffering from alzemir disease (dementia) which is on the some extreme level by the tortures of my elder brother and mother. They are not seeking a professional help from doctors. As a younger brother when I said why not we go for some professional help of some good doctors. My mother and brother said you just sit back we don't have a time for all that stuff. We want him to get die asap so we can take away his whole property and everything and when I rudely said to my elder brother oyeeee iske aagey kuch bola Na he was getting physical with me and when I hit him mom interfere so I want to say if they can think about my dad like this then for me it will not take a minute for them to do anything tomorrow anything can happen.