It's telling that all these things that excite Mary have to do with meeting other people. Mary increasingly understands that she's not the center of the universe, and if she allows herself to befriend others and show interest in them, her world can be richer and more fulfilling. Her question about the scullery maid reinforces this, as it shows that she truly cares about someone else—though perhaps she knows that the explanation of the scullery maid’s toothache is just a coverup for a more intriguing secret.