I agree with the first answer. Also, if the bride and the to be sister in law aren't close, that's a reason why she hasn't been asked to be in the wedding party.
The other day I gave her one to suck on. I held it the whole time- I didn't let it go, or go all the way in her mouth at all. I told my mom I did that and she said my daughter might break out because of the acidity in oranges, which I wondered about but my daughter really seemed to like them...