Wow, that is an awesome story! I am a Catholic convert of 3 yrs and also from MO!! Welcome back to the Church!!! I agree, the only way to be 100% for sure is to of course talk to a priest. BUT, being that I am in a similar boat I can TRY to guess what the answers will be if that will help…
1) Since you left the Church and are not in “good standing” with the Church you will probably need to go through part of the RCIA process, most importantly, reconciliation and have a brush up on Church doctrine and then be confirmed. After your husband has competed the entire RCIA process (will not have to be baptized again if he was baptized in a Christian Church in the name of the Father, the Son…) then your marriage will be validated by the Church. A lovely, simple, little ceremony. Even though I converted after marriage, my marriage with my still Protestant husband still isnt valid in the eyes of the Catholic CHurch, so technically I guess I am commiting fornication??????? Yikes.
2) My son will be 3 in June and he is not baptized at all!!! If your son was baptized in the name of the name of the Holy Trinity and you have official proof of that, then that should be fine. That is waht they told me when we registered my son for Catholic pre-school. My husband and I are in the works of coming to an agreement over our son being baptized. He of course does not believe it to be a sacrament.
3) the way it has been explained to me is that as long as one parent is Catholic then the child can be baptized. As soon as my husband “allows” it then it SHALL BE DONE!! After being confirmed then you can go ahead and baptize your baby!!
I’m so happy for you that your husband wants to convert, it will make things so much easier. Sorry to throw a few of my personal stuff in there when answering your questions, I almost feel the need to explain myself, it’s embarressing that my child isnt even baptized. Some people treat me like, “and you call yourself a Catholic????” I hope my opinion/answers helped. Dont be nervous when meeting with the priest, jsut be genuine and honest! So glad to have you with us!! May peace be with you, Gina