My daughter had a friend over today. Her friend is a lovely girl a little older than her. When she got out of the car (we dropped her at home), my daughter said, "She was very nervous to meet you." I asked why, and pointed out how delightful and charming I am. Why would anyone be scared of me? "Well," said the daughter, "she's quite shy. But also she knows your friend who reads your blog and they have talked about polyamory. She's very interested in it."
Yikes. That was my immediate reaction. I quickly checked in that the friend is fine with this, and reminded my daughter that not everyone is as open-minded or smart as her friend. And that's pretty much the day-to-day. My kids are fine. They, like any other kids of divorced parents who get on reasonably well, would like if their father and I were still together. Aside from that, and understanding that we simply aren't going to get back together, they would just like us both to be happy. If we're happy, we're nicer to be around.
My daughter is at an age where the fact that I'm poly and bi makes me cool, rather than weird. I worry slightly that she'll make life choices based on coolness rather than considered thought. But then I think I've done my best to make sure can think for herself, and is brave enough to make choices that are right for her rather than what her parents want or society expects (which are not mutually exclusive but not necessarily always in step). My son tends to think I'm weird, but he, too, sees my choices as valid and acceptable.
As far as my children are concerned, my being poly means there are more people around who care about them, and about me, and provide us with support, love and plenty of fun. I am honest with them about my relationships, and about their ups and downs. I hope that they are learning that all relationships are different, and that there are ups and downs in all of them, and that these things can be dealt with. I hope that they are learning that we can't predict how our life is going to go, but we can be kind to ourselves and to others, and sometimes that takes us to interesting places. I don't know for sure. Parenting is quite a hit and miss affair most of the time. My kids seem nice. People seem to like them. So I guess it's going ok so far.
Practically, poly life is easier when the kids are away with their father part of the time. There's only so much time and energy in a day, and kids are demanding. I probably wouldn't be able to sustain the number of partners I have if the kids lived with me full-time. On the other hand, if I got my dream of having all my partners, and their partners, living together in one (really big) house, there'd be lots of people to fetch and carry and feed and entertain and otherwise help out with the kids...
And then there's the issue of being outed by your kids. Many poly folk I know live 'semi-out' at best. For many reasons, not least because it gets boring having to explain things to people all the time, I tend to not be out to the whole world. And, certainly, kids, especially young teens, can be wildly judgemental. My kids have already encountered backlash at declaring themselves atheists. I can imagine they'd get a lot worse if kids (and parents) knew their mom had several partners, not all of whom are guys. So we talk about keeping it quiet. Also, it's my private life. There's no need for all the kids at school to know about it. But still, things will happen. Some kid will be friends with someone I know who reads my blog and has mentioned it to them. That'll happen more as the kids get older. And that's ok. As they get older they have to start making life choices. And if their choices are better informed and they have more open minds about their options, and they know that whatever they do they should respect themselves and those they are involved with, then I've done my job well and I don't care who knows it.
My kids are awesome, and I have a great relationship with them. And their father is a remarkable man, who is happy to have them involved in my poly lifestyle as long as they know it's not the only option (which of course it isn't). I think everyone thinks their own kids are awesome. Whether they're emotionally and psychologically prepared to know about your being poly or about your sexuality depends on what you've taught them as they've grown up. And on how honest you are prepared to be with them. You've got to be straight with them. Don't beat around the bush. Obviously, I don't discuss my sex life with my kids, but if they ask me if I'm having sex with a particular partner, I'll tell them. If they ask me how to open a condom packet, I'll tell them that too. Wouldn't have told them that when they were seven, but they'll need to know if, if not now then within too few years. Condom packets can be surprisingly difficult to open, especially if you're nervous.
The caveats would be the same, I think, if I were mono: don't introduce someone new as your partner if you're not sure they're going to stick around. Don't put up with people who have no respect for your children or your relationship with them, no matter how cute they are. Don't force your children to spend time with someone they're ok with but don't have a great time with. And don't expect any of your partners to parent your children unless and until the relationship between the two of you is at a stage where that becomes part of your lives together.
Take it slow, be honest and everyone will be fine. Poly doesn't hurt kids. Bad relationships, of any stripe, do. But you knew that already.