It was a rational scheme, to be sure! but from what the report of their engagement could originate, Elizabeth was at a loss to imagine; till she recollected that his being the intimate friend of Bingley, and her being the sister of Jane, was enough, at a time when the expectation of one wedding made everybody eager for another, to supply the idea.
– Jane Austen
Pride and Prejudice, Chapter 57. Elizabeth ponders why Lady Catherine took the trouble to journey from Rosings for the sole purpose of breaking off Elizabeth’s supposed engagement with Mr. Darcy. She wonders where the rumor of her engagement came from. She speculates that her sister Jane’s engagement to Mr. Bingley had prompted talk of a Darcy/Elizabeth wedding and that had reached Lady Catherine’s ears through the Collinses.