What happens to the relationship between Mia and the other girls, Rose and Lissa, in Chapter 6?

The conflicts between Rose and Mia, and Lissa and Mia, escalate in Chapter 6. Lissa and Rose suspect Mia of playing a mean trick on them. Mia makes some snide comments at them. Rose finds out that Mia's parents are servants, and she suggests that Lissa start dating Aaron again to put Mia in her place. Lissa does not want to get back together with Aaron.