Is it permissible to give zakat on agricultural produce to one of the unemployed heirs, knowing that the inheritance has not yet been divided?

It is not permissible to give to a son from the Zakat obligatory upon his father. However, if Zakat becomes obligatory on the wealth after the death of the deceased and before its distribution, it is not obligatory upon anyone unless the share of each heir reaches a complete nisab. At that point, it is permissible to give to a brother from the Zakat if he is among the categories for which Zakat is designated, as mentioned in the verse from Surat At-Tawbah.