We are trying to finalize our guest list so we can get Save the Dates sent out. There are a few co-workers that I am inviting and I'd like to invite our former supervisor. Our office has about 10 workers. I am inviting 3 of them (one of them is in the wedding). The four of us are pretty close and sometimes do things outside of work (I met my FI because of the one co-worker). I want to invite my former supervisor because we are all pretty close to her as well and we still get together for lunches. Would it be tacky if I asked them to keep it quiet that they were invited for the sake of saving the other co-workers' feelings? It's not that I'm trying to hide them; that's definitely not the case. I don't want the others feeling like they're not good enough to be invited but I don't want the 4 that I am inviting to feel like I'm trying to hide them. We have a tight budget, so I can't invite them all.