By the way,

来源: 于 2015-11-30 13:04:46 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

did you get your US citizen before your child turned 18 years old? If yes, then your child was automatically a US citizen from the date you became a US citizen, so he just needs to file N-600 to get his Certificate of US citizednship now, and not need to file N-400 to apply for the US citizen.