My Son needs an ITIN. We are in the US on a E2 visa. Can we apply for a ITIN with a COPY of our last tax return? as we have already submitted this years.

We are in the US on a E2 visa and my son is not eligible for a SSN. Now he has no medical insurance as he cant be insured without a ITIN. we have already submitted out taxes, so are we able to apply for a ITIN with a copy of our completed tax return?