She really annoys me in a way that her mother does not. She really sort of...imposes herself on Elinor. Mrs. Jennings has at least known them for the space of a few days before she started being "vulgar". Charlotte just immediately decides that they're all best friends, and goes with the assumption that the Miss Dashwoods would accept her friendship and advances on the virtue of her being connected with the family. What was worse, in my opinion, was that I'm sure Elinor and Marianne assumed that Mrs. Jennings had gossiped all about them in letters, but she confirmed it so quickly after meeting them.

And the thing is, I'm sure that news traveled fast in those days, as it does nowadays, but there are ways of pretending that someone didn't gossip to you about delicate subjects.