Tax Relief Refund check.....or is it?

Well, I've got a refund from us treasury totaling 600.00 this morning which is 04/30/2008, question is, why? Is this my tax relief refund from IRS? And if so, why do we only get 600.00 Me and my spose make less than 80 k together annually and we got a 2 year old child shouldn't we get 1500.00??? Please let me know...........(this is exactly what it saids in the dep. description...US TREASURY 220 TAX REFUND 043008