In ch.7 we are told:

Mrs. Bennet was prevented replying by the entrance of the footman with a note for Miss Bennet; it came from Netherfield, and the servant waited for an answer.

A while ago there was an L&T discussion about what servants the Bennets might have had, but I can't remember if a footman (footmen? Did they always come in plurals?) was among them. At first I thought "the footman" belonged to Longbourn, since he came into the breakfast room without being announced, but then it says that "the servant (presumably from Netherfield) waited for an answer". Or were there two servants involved - the one from Netherfield waiting outside, and the Longbourn footman bringing in the message to the family?