DW and I were discussing this very issue over ice cream last night. From past experience, we have decided that our costumes need be light and airy. Alyssa did not do very well with her heavy mouse costume last year to match our Cinderella and Prince Charming (and we were a little yucky by the end of the evening). So, this year we thought we would go as Dalmations: me-Pongo, DW-Perdita, and Alyssa-one of our puppies. We plan to get some white shirts and pants and put black spots on them. We'll make some spotted ears to attach to headbands. And add some collars with our names. Still debating what to do with our hair to make it white with spots. We'll add a little black makeup to our noses. The original thought was DW as Cruella, me as Horace (Jasper if I get back to the gym), and Alyssa as Perdita. But that would not serve the "light and airy" requirement.
Another thought: Peter Pan, Wendy and Tinkerbell. But, I don't think I'm ready for the tights.
Kevin