My husband has a work permit and we have dependent visas to be able to stay here. We would like to bring over (USA) my biological child from another marriage (his step son). My son is 14 turing 15 in August. The school my husbands work at does not know what documents we need. We will go to immigration to ask before we fly to the US for vacation. But what documents do we need to be able to attach him to my husbands work permit and visa (since he is not his biological son)?