Maybe I'm misunderstanding your posts. Haven't you been married for 5 years, and have 4 kids? Aren't they all then under 5 years old?

They should no nothing about any of it. If they heard about it, they shouldn't know what a postnuptial is, unless it was explained to them (and it shouldn't have been).

"Should I still try to paint my husband as a very honest, genuine person? They see it , I can not lie to them"

So, are you going to tell them your favorite sexual position? Or, how much you get paid on a job? No! Some things are not told to kids. What you may not realize, is that when you paint either parent in a negative light (even if deserved), it is damaging to kids. Go to google, and read about parental alienation syndrome.