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If you contact the VO like everyone suggested, they will tell you which forms you need to re-do. Your situation is a bit uncommon here on the forum, since your wife cannot pass her Canadian citizenship to your child, so the child needs to be sponsored.

I honestly don't know how to add a dependent on an application that is already in process/processed. You need to contact your VO asap.
 
My file was just sent to Ottawa and I'm going to be induced due to medical reasons on the 13th of August. I am having him in the States as I still have medical care there. What to I need to show or tell the CIC? I am going to get my son's citizenship set up as soon as I can, I've already looked into that.