Woman's inheritance of ancestral property

A Syrian Christian woman from Kerala, and want to get my ancestral share of property. Briefly, the property an acre of rubber and cashew plantations with a house that was in my paternal grandparents' name; grandparents died in 2005 and 2008. Their 2 children, my dad and my uncle, have 2 and 3 children, respectively. I had a registered marriage and received no streedhanam. Found out recently that my uncle registered the property in 2016, based on a will that has not been shared with my brother or I, in his son's name. My mom had been staying with my paternal grandparents in this house for 12 years from 1967 to 1979 and since 1997 until now. My parents separated in 1998 and my father has agreed to give me a power of attorney to claim his share of the ancestral property. In this past week, my cousin brother has threatened to evict my aged and infirm mother claiming to be the owner of the house. I want to claim my share of this property as is my right and contest this will that was not shared with my brother or I. Please advise.