What is the law in abu Dhabi in regards to the...

Regarding the inheritance, it is divided between your father’s wives and between you and your sisters. With regard to your mother, it must be included in the family book at the Civil Status and Passports Authority, as she is the legal wife of your father. If your father refuses to register her, a lawsuit can be filed against your father through your mother.
In the event that all or some of the heirs refuse to divide the inheritance, any of the heirs can resort to the judiciary and file a lawsuit to divide the inheritance according to the legal shares, as it is necessary first to extract legal inheritance information to prove the shares of the heirs. The rest is required of him until the inheritance is accurately determined, and if that person refuses to submit documents or papers indicating the inheritance, a report can be issued against him to oblige him to submit them, otherwise he can be transferred to a criminal trial