My father died a year ago, leaving my sister as executor of will and his estate and my mother the sole beneficiary. My father made my sister a director of one of his companies after he was diagnosed with demithia, she has since burnt his medical records. She has told my mother that she must sell a property that is in the company's name. My sister owns the property beside mum's and I believe she is going to buy it herself. She has told my mother that to transfer the property from the company name into hers will cost too much, the property is worth over one million, and is currently rented out. My sister also lives rent free (separate houses) on another property with my mother, and my mother is scared that if she doesn't do what she says, she will turn against her. What can I do to stop this abuse?