Kemp, I think I would tell the W, at least at this point. As time goes on maybe not. I guess really the kid intro is not our business unless it negatively effects the kids. However, I think since this is going to be the first intro for the W (and maybe the last the way there are going) it is something that should be adressed as a family, at least in my opinion. It appears this is not how it typically works though.
I think MHL is right, it will likely be a casual intro as a new friend, and then I will hear about it after the fact. If that happens I will have soemthing to say. I want to know everything that is going on in my childrens life and I do not want to hear about things after the fact.