My husband is overseas and hasnt paid any taxes, will i recieve a income tax refund for non-taxable combat pay?

He says we will, so does everyone else, but I dont see how that is possible if he hasnt paid in any taxes nor will he cause he wont be back til after January. He thinks that it will be close to $8000.00 cause of our 2 kids. Do you think he is correct? Also, is there a certain limit on the non-taxable combat pay in order to recieve the earned income credit for our two kids? please help I am stressed out? And is there any credits for having a newborn, i delieved on 3/24/2009? Thanks so much for your help!