In On The Banks of Plum Creek, one of the things that really cements the rivalry between Laura Ingalls and Nellie Oleson is the two competing parties the girls held. One party, held by Nellie Oleson, was called the town party, while Laura and her sister Mary held what they called the country party.
The story of the parties is also contained in Laura’s original manuscript Pioneer Girl. It does confirm the fact that the girls held competing parties, that were very different from each other. And because it was in the original manuscript this shows that this event really did happen, and it wasn’t one of the events more dramatized for publication in what would become the Little House books.
The events in both of these parties also really highlighted the differences between the behaviour of Nellie Oleson and that of Laura Mary and the rest of their friends, and confirms Nellie’s behavior as being rude and downright mean.