My father has passed away without any will. We are three brothers and one sister. We have a building with a shop on ground floor attached to where we live. My second brother stays in the first floor house for which i have put around 4 to 5 lakhs while constructing. The eldest brother opted to go out and now wants a share in the property. My second brother has been taking the rent of the shop and took 1.8 lakhs (1 lakh was taken in the beginning which was put for construction) extra advance from the shop keeper from which i did not get a penny. now i am asking them part of my money in the advance. they are not giving that and instead are trying to use it to construct second floor. First floor is much bigger with good light and ventilation while ground floor is smaller, in the sense ground floor property value is less than that of first floor. What should i do to stop them from constructing and to get my EQUAL share of the property??? 
how about my sister..how much right does she have in it..my second brother has all the documents..do he have any right to do things without my knowledge..pls advice
