K.
You probably can't wait until christmas to do this, but my cousin bought 12 christmas ornaments in blue and pink and put a piece of paper in each one. Only one had the paper with the sex of the baby. We all got to go around and open our ornament and see if it was us. It was great fun and of course most of us cried tears of joy when we found out what she was having. Maybe you can do some sort of variation?