Is it permissible to distribute the inheritance of the second wife to the grandfather among some of the heirs to the exclusion of others, especially since her assets came from the grandfather's money?

The wife of the grandfather is inherited by her heirs, such as her sons and daughters. Her husband's children from other wives do not inherit from her. Your father and your full paternal uncles are not among her heirs. What the grandfather gifted her during his lifetime became her property after she took possession of it, as well as what she inherited from him. If the grandfather has passed away and all his assets are in the possession of the second wife, then your father and his brothers have the right to inherit from their father's estate, not from the second wife's estate. If the grandmother died before the grandfather, he inherits from her, and upon his death, his estate is divided among his heirs, including what he inherited from his wife.