A Widow mother had out of her own money had bought a 500 sq yard house in delhi. she had 3 children , 2 sons and 1 eldest daughter. she used to live with her youngest son, eldest daughter used to live out of the city and second son used to stay at some other place with his own family and was not in good terms with mother.Unfortunately he was handicapped / walk with support of one person but during his good health days had amassed good property and used to live a good life. The mother before her death had written a unregistered will whereby she had given the ground floor and first floor of the constructed portion in the said plot of land entirely to younger son, who continued to occupy the house , since he took care of the mother during her illness and supported her thorught her early days. Mother seeing the health of the eldest son , left the roof of the top floor to her elder son, roof is empty with no construction on it. Now elder brother is claiming 50% share in property by virtue of owning the roof and the mcd allowing third flloor construction. the younger son is saying that this will defeat the intention of mother who wanted to give the entire share in constructed property to him, with just a token to elder son. the will only uses the word 'roof of top floor to elder son', without specfying for what purposes it can be used neither dose it specfied about the third floor , as at the time of writting the will 3rd floor was not allowed. since the building is 35 yers old build in parts , structral saftey is also in question.
Please advice who own what and how this problem can be solved.