I am from Telangana. In Telangana, there is no rule of taking date of marriage as parameter now. Earlier it was there. Now the women is entitled for equal share even in the ancestral property. The property which your father holds is ancestral in nature and still your father is alive, the sons and daughters can claim rights from your father to their respective shares. Your mother cannot claim.
But if your father died intestate, his share will be divided into four parts (one son, two daughters and wife). Hence, wife is entitled to 1/4th share that too from the share of his husband. For further clarification contact my email.