I have replied to your another query (mother query). kindly note.
According to latest development in the incident of death of your mother, you can now have right to file partition suit. If you do not bright to light the unregistered will, the whole property will be distributed according to succession Act and all the children of your expired brother will get right. Hence, you will get only small amount of share. Consult your brother who is having possession of the will and proceed.