My stepchildren (wife's children) have known that mom has other men since they were teens. Ever since I came into the family and they were Pre-K, they have grown up seeing mom partying, dressing sexy, having lots of friends over. Mind you she has been a very engaged mom. So it has been normal for them to see many guys besides myself around mom.
Of course they never got to see what goes on beyond that. As they grew up, she had to play outside the house. but she still brought them home. I used to travel extensively so it was a bit of a help to have them around house to help out with a BBQ or even kids projects!
Now that they are adults and have their own partners, I think they have put 2+2 together and figure that its pretty obvious that I am in the know.
What is exciting is that many of her female friends have also figrued out that I am a willing cuck. Birds of a feather flock together. So the majority of my wife's female friends are also sluts and hotwives. And her male friends are ex bulls or friends of the bulls.