J.B.
W.: As a long-time fan of Cirque (I'm going too!), my thoughts would be that although she will certainly be interested in the lights, music, and acrobats, with an 18 month old, her interest will be shortlived, and you may have to leave the performance early. My suggestion would be to get a sitter so you can go to the performance and really, truly enjoy the experience with no distractions. Good luck!