Good luck to you both, and what a fantastic gift to give your son!
It has been over 3 1/2 years since I have had a cigarette. I was very proud this summer when I saw my doctor and she changed my status to a "non-smoker" in my chart. It is not easy, but it can be done. The only advice I can offer is this: You have to go into this knowing that you will never touch a cigarette again. Ever. There is no, "I'll just have one" or "I'll just take one puff". The trade off is better health and a longer life though, so it is worth it.
Sorry about the speech. I'll be rooting for the both of you.