The question is that It doesn't matter what culture or how many father's there were. Gestation with humans is 9 months and normally breast feeding makes that next pregnancy wait a while longer. Anyone can do the math, so when was the first born?
I could be wrong about this, but I'm guessing that whatever number of children the OP is claiming, they aren't all hers by birth, and that some originally belonged to the husband and to the boyfriend by different mothers.
I once knew a man who would tell you he had 5 children, but that's because he married a woman with 5 children, and he hadn't biologically produced any of them.
This whole story reminds me of a girl I used to know.
She had multiple kids by multiple fathers, and was currently with the father of the youngest and talking marriage. However, it was later rumored that he was cheating on her with another woman who also had multiple children by multiple fathers. The boyfriend vehemently denied that he had ever slept with this other woman.
Some time later, this second woman had another child, and so the first woman, wanting to test him, presented him with, "You know, I saw (the other woman) and her baby the other day, and that baby looks exactly like you."
She hadn't actually seen this other woman, nor had she seen the child. But he immediately answered, "I swear, it isn't mine! I'll take a paternity test to prove it!" And she looked at him and said, "If you've never slept with her, why would you need to take a paternity test?"
Hook, line, and sinker.
(I don't know if he turned out to be the father or not -- I didn't hear that part of the story.)
Now I know it sounds like something straight out of the Maury Povich or Jerry Springer show, but this was the daily norm for many of the girls I worked with (and most of the fathers of their kids wound up in jail.)
The most ironic thing is that one of these girls had a prominent relative who headed a local church, and so the whole family claimed to identify strongly with God and was in church every Sunday. But apparently, there was no such thing as sexual sin to them unless it was textbook adultery. Everything else seemed to get a pass, so they all thought they were right with the Lord.
I asked her once what her church's sermons were about, and apparently, there were certain things they focused on that stood out to them as "sin" and so that's all they talked about. Stealing and murder were apparently heavily preached against because it was an area where shootouts were common. Other things they were told was to avoid hard drugs (but weed was seen as ok, and this was way before any state had made legal exceptions,) and try to avoid joining a gang. These were seen as the biggest problems in the community, so apparently this is what the churches focused on. (I keep saying "apparently" because I'm only going by what I was told -- I never actually attended these churches myself to hear what was taught.)
I was genuinely shocked, as I was just a sheltered kid from a small town in another area.
I have often wondered if one of the biggest hurdles to evangelism and getting people nowadays is trying to get others to come into agreement of what sin really is.