Child Credit

[weblover78]

I have personal question about tax return we currently have 2 childern but want to have more in the future..and while working in the US, we both filed our joint return every year and we received child credit each until 2007. I have been living outside the US since 2004 and my wife neither filed her taxes noe she received any child credit this is bad from IRS site... I would like to know following things

1: Can we file our taxes for these years, although my wife did not/could not work.
2: Are we eligible for late return and child credit
3: Is there any penalty for not filing, and is there any exemption for folks like me who stayed out side the US what other option we have to fight with Internal Revenue Service?