I second the praise and girls often do well if they think they are helping, so when it comes to going out ask her if she can carry something to the car for you or her brother, can she sit in her seat herself, star charts, little rewards for doing the right thing, she does'nt need to sleep but she does need to relax in her room, so books, toys, some special things just for that purpose and thats the only place and time she gets them.
Good luck, it might just be a stage and in a month or 2 will pass, as do most things.