I just flashed back to the days of having only 5  kids and one on the way.  We were moving across the country from Delaware  to Washington and opted to drive.  Lots of clothes to keep up with and our  oldest was only 8, so most of the laundry duty was up to me.
The way I kept up during the trip was to pack a  clean outfit for each of us in a trashbag with a twist tie.  Each night, we  would carry one bag plus the toiletries kit in to the hotel.  Everyone  would shower/bathe and the dirty clothes went back into the bag and we would tie  them shut to keep clean and dirty from getting confused.  When I had the  chance to do laundry, we'd repack the clean clothes and put the twist tie back  on.  
This kept us from having to carry a  suitcase/backpack for each family member in every night and really helped to  maintain my sanity.  Plus, it helped me to stay on top of the laundry  situation knowing how many clean outfits we had left and when we'd need to do  the washing again.
Oh, in case you're wondering, we never minded letting our kids sleep in their clothes! ;)
Oh, in case you're wondering, we never minded letting our kids sleep in their clothes! ;)
