Family and situation
Mrs. Long's nieces are two or more young women who appear to be visiting their aunt in the neighborhood around Meryton, Hertfordshire.
They seem to be near-permanent residents of the area, suggesting that they either happen to be staying for a long time with their aunt or live with her on a more permanent basis. It possible they only stay with her once Charles Bingley comes to the neighborhood in the hopes of attracting his attention (they’re never mentioned in the first several chapters of the novel).
Character
Mrs. Bennet says after entertaining the pair at Longbourn towards the end of the novel that they are “very pretty behaved girls, and not at all handsome” and that she likes them “prodigiously.”
One of them could have been the girl who prevented Darcy from making chitchat with Lizzy over coffee, saying "The men shan't come and part us, I am determined. We want none of them; do we?." However, this is never confirmed in the text.
