回複：Thank you very much. Further question:

we need the visa to be sent to us as we could not stay and wait for it around the Embassy. Thus how should we provide the address for them to send us the visa-passport?

-Then, you can use the address such as mail box you can receive it after the kid's visa is approved (you may need to fill another form for the passport shipping during the interview. check the website for more information). Please note that the address in the DS-160 can be different from the address you want to use for receving the visa/passport.