Clarification requested on inheritance

My sister-in-law is a spinster. She has three sisters and one brother. Her aged mother is also alive. One of the sisters is a widow.

My s-i-l is critically ill and may not survive. She has some money in her bank and in Fixed Deposits. She is in very bad shape and cannot move or sign. She has no will.

I would like to know who will inherit her money as per law. While nobody is after her money, we would not want it to be forfeited by the bank.

Kindly guide and oblige.