Regarding Poland's Visa application of Minor child

Dear all, my query is regarding Visa application of minor child.. I don't want to take my child (4 YO ) to consulate. Can I submit her application form as well.. consulate rules says yes, but need to attach authorization letter (pl see pic attached).. anyone know WT is the letter about..TIA

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Hi,

Yesterday i applied for National D visa and i inquired about dependent visa for my wife and kid in the counter.
lady at the counter replayed no need to bring kid for visa submission but dependent visa for wife i should be in person there with my wife for visa submission, if i already traveled to Poland then i need to get authorization letter from Poland authorities and dependents need to submit that authorization letter with application .

have you submitted the application for dependents. if yes please tell me the procedure.