Get a good attorney. Get all agreements in writing. Put yourself and kids way before him. Know it sounds expensive but the grief, aggravation in the future is well worth it. My oldest was 9 yo at the time when my attorney said let's put in he pays for college. Huh!? When that time came he had a great job, didn't want to. But oh well we had a legal agreement. He had to put both on his health insurance within thirty days of getting it. Don't assume how it is today is how it will be in the future. We both had to keep the kids as only beneficiaries of life insurance, will. Even if he remarried (he did shortly) or had other children.(he thought he did!). Even if he doesn't have life insurance today.Whether or not he is working now, get child support & alimony ordered. Neighbor married a divorced man. After a few years, put his name on her house. Shortly after court ordered the house sold to give his kids the back owed child support. Really bad part was he had told neighbor he had never been married when I'm fact she was wife #5.
Now's the time to be greedy for your kid's future. If he doesn't ever go to work, receive an inheritance, win the lottery, you will work it out somehow. If he does, he will be forced to contribute to his kids welfare. Take care.