My aunt (my mother's sister) is the oldest of 7 siblings (3 brothers and 4 sisters) , of whom one brother has passed away leaving behind his family members and all other siblings have kids. My aunt is an uneducated child widow and has no children.
She has never relied on her brothers for the last 40 years and has been living along with her 3 other sisters and their families and they have been supporting her for food, shelter and all medical necessities. She did some small scale home activities when she was younger and with the money obtained and saved, she has acquired some properties by herself and all these have been willed to her 3 sister's children. She is 85+ years old now and in frail health. In case of any eventuality tomorrow, who are her legal heirs? There is a certain registered firm property under litigation and she is a partner of this firm. In case of her death, is there any documentation she can prepare right now to say that none of her legal heirs can claim or cause complications while resolving this property's issue? Please advise.