For matter in court your own lawyer that has seen whole case file and record can advise you the best.
Copy of Death certificate of deceased father can be provided to your lawyer and to court.
Do you have evidence of property being self earned/acquired?
Is husband of your Bhabhi i..e son of your deceased father and your brother alive?
The property is at which location?
Is the WILL registered?
Has the WILL been properly acted upon i.e. either after NOC of all legal heirs, or probate from probate court.