After many miscarriages, we are unable to have a sibling for DD (3). DD has asked to have a sibling, and has been told gently why she can't have one, but clearly won't really understand.
I am perfectly fine with people asking me whether we are going to have any more children, as it is a natural question to ask (even though I always have to paste a smile on while answering), but people quite frequently ask me when the next one will be on the way while DD is there.
I don't think that this is appropriate, and wouldn't do it to anyone else, just in case there is a problem of some sort; do you think IABU?