How did you decide to have a second child or NOT?

Try having another. The joy and love that your family will receive will eliminate your fears. Let life triumph. Do not think so much about the what if's? Not knowing is what makes life exciting. Your arguing will never go away. It sounds that you have a normal relationship. Would it not be boring if you agreed on everything? Sometimes it is fun to argue and especially make up afterwards :) It sounds like your husband is supportive and that you will have help available. What kind of life do you want in your elders years? One filled with many kids and grandkids, or one filled with few? Answering this final question should help you decide. Good luck and God bless.