回复：请教 863211老师， Pijiang 老师关于公民婚姻绿卡. 请帮助。

I am a US citizen and married to my wife while her child is 19 and in University (In Canada). I am preparing to file green card application for my wife and the child. My question is:
Can I sponsor the child for green card as Immediate Relatives of US Citizen?
-No.You can not sponsor your stepkid's green card application neither directly or indirectly (you has nothing to do with the kid in the GC application) because your marriage occurred after the kid turned 18 years old.

So, you only can sponsor your wife's GC application, not the kid.