How do you hide a group from just one person on Facebook?

[Dragonwars]

So I am making a Facebook group as part of a present for my friend. Not sure how exactly to hide it. I have put it as secret so it doesn't show up in wall posts to her and have blocked her from joining but if the group is on secret other people when I invite them can't see exactly what it is and they cannot invite other people (I don't think) what are my options? Will the ban alone stop her from seeing when her friends join the group?

[╘ JONATHAN ╛]

Edit your Privacy Settings:
http://www.facebook.com/privacy/?ref=mb#...cy/?ref=mb

Hope I helped,
[Jonathan]