Congrats on number 7. We have number 6 in the chute. :-)
Another reply you can use when people ask the always inappropriate question "Are you done?" is: "Why do you ask?" Of course you do this with a smile, and I would only use this if the person was being obnoxious about it. Thankfully neither my wife nor I have had to use it. Most of the time when people ask this question they are being friendly and not really aware of how out of line this question is. I often just shrug my shoulders and say "Who knows" while smiling. I then usually go on to make some joke about having a basketball team or now with 6 that I don't have to play goalie anymore. Usually this causes a smile and the whole uncomfortable moment passes.
With the "are you done" question my husband used to emphatically answer "YES". After our last surprise he sheepishly will say, "I don't know."