Legal rights of propety

1. Mr X purchased a land in 1952 in Delhi.Mr. X is have 2 sons and 2 Daughters I.e. Elder Son A Younger Son B Elder Daughter A Younger Daughter B 2. Before 1965 Mr X was living with Younger Son B. 3. In 1965, Elder Son A came to Delhi because he was suffering from Cancer. He was having 2 Legal Heirs i.e. Elder Daughter AD and Elder Son AS. Elder Son A Started Living in the 1/3 of the Property 4. In 1967, Mr. X done a Registered Will in the Name of his Wife Mrs Y. in WILL, he stated that after my death the whole property will belong to her and if she wants she can give the Property to Legal Heirs 5. In 1968, Elder Son A died as he as suffering from Cancer and Mrs Y(Wife of Mr X and) died. 6. In 1969, Mr. X done a another Registered Will invoking the Previous WILL which States that A. Whole Property Owner is Younger Son B B. Legal Heirs and Wife of late Elder Son A will be living as License in 1/3 of Possession and Can be Evicted anytime by younger Son B. Younger Son B was treated as Licensor and Owner in WILL 7. In 1971, Mr. X died. Legal Heirs of Elder Son A i.e. Mr AD has taken the possession(Started Living) in 1/2 of the property. Then There was Oral Family Settlement that Property is divided into Equal Part between Mr. AD and Mr. X . No Written Document was made. 8. In 1977, Elder Daughter A and Younger Daughter B(Other 2 Legal Heirs of Mr X) done a Registered Relinquishment Deed in the name of Mr AD and Younger Son B giving there Whole Ownership Equally To Them. 9. Younger Son B is having 4 Legal Heirs (Elder Daughter BD1, Elder Daughter BD2 , Elder Son BS1, Elder Son BS2) 10. In 1994, Younger Son B died. 11. In 1997, Legal Heirs and Wife of Younger Son B has done there Own Relinquishment Deed giving the property half/half to Elder Son BS1, Elder Son BS2 and also stated that they are having the possession of the Property. But they are actually having possession of half of the Property 12. Sons of Younger Son B are not having any Source of Income so they want to have this property in any way 13. Mr. AD has done the Mutation of Half Property in his name since 1998 and paying the Electricity, Property Bills from Many Years. 14. Also Mr. AD has Revamped(Re-Structure) the home in his Half around 2002. Can anybody help me about Mr. AD can take Title of His Half and What is possibility of wining the Title? Please help us as we are really feeling alone.