Thanks again visanutz. So it's okay to go ahead and use our son's new name and ssn although the ssn is currently in his old name? Will this not cause some kind of mix up or something with the government?
If you have any document showing the legal name change, use the new name and old SS card.
If you don't have any document, use old name + old SS card. Once you get the passport or name change document, update the name with your health insurance by giving them a copy of the document/passport.