Request for advice about property law

I am muslim and wouldlike to ask you help with my situation ,My monther received house(3.305cents/1440SQft) from her mother And my my mother purchased another plot and constructed a house. we are 4 brothers.I am elder.My2 younger brothers registered 50+50 in constructed house on their names with an agreement to share the inherited house to me and to another brother almost 10 years back. In the inherited house My mother lived in one portion and off portion another brother is living. Recently my mother passed away without making any will or registering the house in our names. Inherited house property tax and electricity bills were used to pay on my mother's name. But one of my younger brother secretly mangedand ,changed electricity bill and property tax on his daughter name without knowing any body when mother was ill and on bed.Now both younger brothers demanded for 4 shares in inherited property. Kindly advise me about my options. 1.What are my options?