The Odd Couple in Our House

Since the girls took apart their bunk bed, we decided we're not going to put it back together -- despite the fact that they woke up the next day with renovators' regret. The blond twin has been asking for her own room for months now. She brings it up about once a week. Since they took apart the bunk bed, we decided it was a good time for a trial run.
They sleep in a large room we created from two small rooms. We kept the windows and closets, but removed the center wall and closed up a door. To give them each their new space we put the dressers in the middle to form a divider. Their beds are on the far side walls. Their spaces are further defined by the curtains and matching rugs they previously chose. Now the blond twin lives on her side with her blue curtains and shag rug. The brunette twin resides in green splendor on the other side of the dresser wall. They are happy girls.
When they spent the night at Uncle Dave and Aunt Sue-Sue's I stood in their room admiring their decorating. I also noticed one very big difference between their rooms. The blond twin had everything in order. Her bed was made. Her dresser had everything lined up neatly against the mirror. Her dolls and stuffed animals were lined up neatly at the foot of her bed. Then I looked at the brunette twin's room. Her unmade bed had dolls and critters all over. There was stuff in a pile at the foot of a dresser. She had a bag of dolls clothes between her bookcase and her closet.
All I kept thinking about was the show the Odd Couple. Remember it? Two middle age men were roommates. One was orderly and neat. The other was messy. A lightbulb went off in my head. The reason the blond twin wanted her own room so badly was she wanted her stuff to be neat and orderly. The mess we saw every night wasn't so much about their day as it was that the brunette twin doesn't clean up after herself. The blond twin didn't want to clean up after her sister anymore, but she didn't want to say that. No wonder she's so happy now.
So far they seem happy to have their own rooms. In fact they call their space "my room" even though they still technically share a room. The nice part is they can still be together when they want. They pushed the issue by separating their beds and it all seems to be working out well -- for now anyway.