For a Hindu female, dying intestate, the succession law for inheritance is:
2.parents (father & mother)
3.Heirs of father & mother.
In the present case, as the deceased was unmarried, died intestate(without keeping any will) her assets will be inherited by the heirs of her father, i.e her siblings .
If there are no others to claim her assets, then her assets will be shared by you and elder brother. But one of you can give a consent in favour of the other if he so desires.
As per the value of the assets, you may have to get a legal heir-ship certificate(if the value of the assets are very less) or Succession certificate if the value is more . I presume that as she had her house property and bank accounts, you may need to apply for succession certificate.
Succession certificate is to be obtained from the district court who has jurisdiction of the place where he person deceased resided. It may take some time to get a succession certificate.
Before that be ready with the death certificate, details and value of all the assets of the deceased, including stocks and shares, gold, silver,etc, bank deposits, landed property etc. Also get the details if the deceased had any liability both statutory and otherwise and to whom it is owed.
There is some prescribed fees for petitioning for succession certificate.
The court may publish a public notice. After waiting for the prescribed number of days , and ensuring that there is no contra claim by any other person, the court may grant succession certificate.
It is suggested you take the help of a known and experienced reputed lawyer. You should also monitor the matter regularly with the lawyer, and be present in the court when summoned by notice.