How we cite our quotes:
In the drawing-room Miss Crawford was also celebrated. Her merit in being gifted by nature with strength and courage was fully appreciated by the Miss Bertrams [...] (7.23).
This novel is, in many ways, a giant running commentary on the whole nature vs. nurture debate. Are people born with their personalities, or are their personalities formed by circumstances and surroundings? The narrator here notes that Mary is naturally strong and bold, which contrasts to the passive and weak Fanny.
"Why, child, I have but this moment escaped from his horrible mother. Such a penance as I have been enduring, while you were sitting here so composed and happy! It might have been as well, perhaps, if you had been in my place, but you always contrive to keep out of these scrapes" (10.27).
Julia is annoyed with Fanny for managing to get herself out of awkward situations just by doing nothing at all. Fanny is never in the thick of things, good or bad. Instead, she's often literally sitting on the sidelines.
Fanny looked on and listened, not unamused to observe the selfishness which, more or less disguised, seemed to govern them all, and wondering how it would end (14.4).
Fanny looks and listens here without interacting. It's almost as though she's watching a TV show. It's notable that Fanny is "amused" by everyone around her. Her amusement implies a bit of arrogance, though – rather than participate, Fanny just sits around and judges everyone else, to some degree.