This is 100% fake.

There was a post on here recently from the perspective of the youngest kid, the story was exactly the same as this until the fight, mom says "how dyou know any of them are yours". In that story the parents made up and forgave each other (there was a lot more drama) but there were some comments saying maybe dad should get a paternity test on the other kids to be sure.

This seems like a red piller's little alternate fiction, especially with the height and dick size comment at the end.