Sister asking for share in parent's property after their death

Last year my parents died in an accident after their death I I dropped my studies and any how managed to married my elder sister in a wealthy family.my parents bank account is been seized after their death because my mother was nominated for next heir. I roughly get 5500rs for my monthly expenses. From last few months my sister is asking for her share in my only house and properties under in his husband pressure who earn more than lakhs per month. What should I do !!!!