In any adult life, if we have kids in our lives, we tend to keep a part of ourselves away from our kids. In a lot of cases with the non-monogamy lifestyle there are a lot of parents that keep that lifestyle away from their kids to the extent that they never let their kids know who they truly are and who they truly love. There are others that keep the lifestyle respectfully away from their children, but don't hide who they are from them.
I have a strong opinion about this subject, which I will share, but before I do I want to express that it is just that. It is an opinion. I do not have children of my own, but I do have children that I live with 50 percent of the time. These children belong to my life partner, who I live with. He raises his children the way that he needs and wants to. I have no say on what his children know or don't know about us or him, but I am left in the loop.
First off, I'll say children aren't stupid. They are much more intelligent than we give them credit for. They are empathetic and feed off of the adults around them. Living with and being close to my partner's children for so many years I learned that very quickly. They know when something isn't right, they always pick up on it. If the parents or adults in their lives aren't happy, they aren't happy.
Another thing that I believe about children is teaching them to be who they want to be and to never apologize or be ashamed of it. If you are truly yourself in front of your children, they can follow by example and see that what they choose for their life is okay as long as they are happy and not hurting anyone. Of course, there is a line when it comes to this lifestyle. Children who are very young can't understand a lot of this. So choosing not to be open to younger children makes sense. There is also adult time and non-adult time. And the people in your life have to be very understanding of this. You always choose your boundaries with what you show to your children, but I think it's important that they see you are open-minded and accepting because you love them. Lead by example and show how accepting you are.
You should always choose what is best for your child(ren) and what makes you comfortable with them. But what does it say about your acceptance of them if you can't respectfully and appropriately share who you are with them? If you can't share who you are and who you love, what makes you think they will do the same with you?
Advocate for your children to be open by showing them they have a choice, and that they should never be ashamed of making it.