The only advice I have is to avoid "if that works" - make your life plans, and be able to discuss the pros and cons of each option, and you are not together yet because you haven't made the final decision on who goes and who stays. Take your son with you to the interview and make sure he sits on your husband's lap. He is the best attorney you can hire for the interview. If the two of you are going to be together for more than just the interview day, a "rehearsal" interview with an attorney is good value - and you can get a reality check on what you say. I hope it goes well.
Your basis for immigrating is not clear. Assuming your USC spouse filed for you as an immediate relative my recommendation is that you tell them the truth about why you are living apart and why it took this long for you to move to the U.S. They will want to know about your bonafide marriage and a child goes a long way to proving you have a real marriage. If you entered the U.S. on a visitor visa and are now adjusting, you might want to check with an attorney about your immigration history and possible fraud issues. Good luck.
Due to the nature of this forum, Attorney Maria J. Marty does not have all the information required to provide legal advice. Accordingly, her responses on Avvo are intended as general and not legal advice.
YOU NEED TO TAKE A LAWYER WITH YOU TO THE INTERVIEW.
The government is very suspicious of 'marriages of convenience.'
Sure, you have a child together. But, in your own words you stated that employment and 'lifetime friends' are more important to you than to live with your spouse ... this is highly suspicious.
Also, as my colleague pointed out ... if you used a tourist visa to enter the US fairly recently, this too could be a problem.
Meet with a lawyer immediately.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.