Legal rights on property gifted among siblings in Mauritius

Hello. I reside from Mauritius Triolet. My father is having some issues concerning his property inherited by his mother long time ago. Now that his siblings are not agreeing of what has been proposed as their mother's will. My father has one brother and three sisters , one who died recently. About approximately 25 years before , my father's mother had serious health issue and decided to then handover her properties among her children. Then, she decided already that the boys will get more that the girls. After being gifted the properties, all siblings were agreed by their mother's will. They even signed the contract of will. The contract of land property was then officially in my father's name. Now, in 2018 , the other siblings came and said that they want more from my father's property as they feel they got less than them. My question is, whether my father has fully right in deciding what has to be done with the property , and can he even disagreed to what his siblings want ? If he disagreed to them, can they go to the court and create legal problems concerning the right of the property? will the property be snatched from my father by them ? Thank you in advance.