My daughter and son-in-law are living in China using Student visas and will be there for some years.

My daughter is pregnant and wants to change her visa to wife when they renew in September. We will bring their marriage license along with the Illinois state authentication to the 1 Erie St office to have the Chinese visa office authenticate the marriage license also so we can send it to them. Will we need to bring any other kind of information or documents besides payment and mailers with us when we come for the authentication?