Here’s the deal: my husband had an affair with a married woman. We separated when I found out in the most horrific way and remained that way for over a year before reconciling. I now know everything about what happened and have moved past it.
Here’s my one problem. After we separated, he continued to see her for several months while she was still with her husband (both of them intimately). She got pregnant during that time and her husband refused to claim the baby was his, instead insisting it must be my husband’s, because it was born handicapped. There was never any sort of DNA testing done and the child was given up for adoption to a beautiful family (yes, I met them). My husband just wants to forget the whole thing and let it be, but I honestly don’t believe this child could possibly be his. It looks NOTHING like our children but identical to the other woman’s child with her husband. I want a DNA test done to confirm either way before I even begin thinking about telling our children about this other child. Am I crazy? Should we just move on like the kid doesn’t exist? How do I get him to do the DNA test?
LemonVibe 
If you are being sued for child support then yes, have a DNA test. Otherwise what do your children have to gain from learning this? I would get all YOUR legal ducks in a row however and seek marriage counseling right away if you want to stay in this marriage.
He created the mess so he needs to fix it. I would get a DNA test, it’s only fair for the child created, your children if you decide to tell them. It’s morally correct to get it done. Maybe re assure your husband that regardless you’ll get through it if it is. Maybe he’s scared to know the truth
Maybe try to forget about it? I don’t mean that casually