In the first film/book? She volunteered to take her sister's place since Prim was, as Katniss once described her, "scared of her own shadow," and she would've most likely have been killed first. But Katniss knew how to hunt and that gave her somewhat of an advantage in the Games
Katniss does (Katniss is Primrose's sister)
Katniss have her sister Prim a goat.
Tresh saved katniss life in chapter21
Katniss saves Prim from the reaping by volunteering to go into the arena instead of her little sister.Really, Katniss saves Prim from the Hunger Games, not the reaping. When Prim's name was called to come onto the stage so she would be announced as a tribute, Katniss was pulled back into memories. Katniss couldn't stand the thought of Prim going into the Hunger Games, she loved her so much. So Katniss volunteered to take Prim's place, and Prim was saved.
yes
Primrose Everdeen
Primrose, katniss's little sister
Katniss
Katniss lives with her mother and little sister, Prim.
Katniss lets Peeta live and saves his life
Katniss's sister is Primrose(also known as Prim). Prim was chosen for the Hunger Games as a tribute, but Katniss took her place.
Katniss is determined because she thinks in the end she can save Prim (her little sister.)