Whenever I see one on a child, I say "happy birthday!" and so does most CM's and other guests. It gives kids a lot of attention (which is what most kids want for their birthday!).
I hear that you can get them at guest services at each park.
I think that your room requests were a different question? You can call and request a specific building. Upon check in, try the request again. They try to honor your request, but it IS only a request.
I hope you have a wonderful time!