There is always a rift between siblings if the parents do not make a will or authorizing someone e.g. syedna/ambanis/SS/MNS/....so dont U think when ppl are living and in gud health they should make their WILL in advance instead of den fighting for upperhand???
Even after making will there can be rift on inheritance by filing petition of undue favorism under both law Hindu code n Muslims code. Will is a tool to prevent property etc going into wrong hands but not the final solution
One can always or free to challenge the will and nomination under a simple clause like unfit ,unfavorable ,bias, and natural inheritance
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They are exceptions, still such siblings in this world exist whose parents had just left a House, a Plot few cash in Bank and a Policy , and they are called Middle class parents their children never fight in court for the property their fights goes within to do Better and remain Independent