Sucession rights of married christian daughter

Hi i am looking for legal opinion on my rights over my parental property. We are three sisters and two brothers. My father died while we were minors and only my eldest sister was over the age of 18. My father had died intestate and the landed property was subsequently (after my marriage) divided between my brothers and my mother with my brothers receiving an equal share of 80% of the original property and my mother getting the remaining 20%. My mother is still alive and had willed the property in the name of my younger brother, but my younger brother has died recently. My younger brother's wife is now trying to get my mother to sell her property and take the proceeds. My questions are 1. Can the property in my mother's name be considered as ancestral as she had inherited it after my father's death? 2. Do I have an equal share/right in the property in my mother's name? 3. How can I claim my share of the property in my mother's name. 4. Was the initial division of property between my brother's and my mother legally tenable as my father had died intestate and we were all minors at the time. 5. What legal remedies are available to me to prevent the sale of my mother's property and obtain my share in it.