Why is Primrose Everdeen important in "The Hunger Games"?

There are a few reasons as to why Primrose (or Prim) is
important in the novel The Hunger
Games.

First, Prim was the initial Everdeen to
be called for District 12's tribute. If Prim would not have been called, Katniss would
never had needed to volunteer to be a part of the Hunger Games in order to save her
sister's life.

Second, the relationship between Katniss and
Rue (District 11) would never have happened if Rue had not reminded Katniss of Prim.The
relationship between Katniss and Rue proved to Katniss that Careers were not the only
ones entitled to alliances.

Lastly, the fact that both Rue
and Katniss (given Prim was the reason this relationship existed in the first place)
have embraced the mockingjay is important because it, eventually, becomes Katniss'
symbol and her unending tie to Rue.