this action rests on the concept that hereditary property consists only of that part which remains after the settlement of all lawful claims against the estate , for the settlement of which the entire estate is first liable.6 the reason why in case suit is filed against all the heirs the tax due from the estate is levied proportionately against them is to achieve thereby two results : first , payment of the tax ; and second , adjustment of the shares of each heir in the distributed estate as lessened by the tax .