The short story is narrated by an unnamed first person narrator in the first person.
First person point of view is when a narrator describes things from his or her own perspective, using first person pronouns such as I, my, me, and we.
First person is closer, but less reliable. We see this in this story, as we hear Sister’s perspective and not Stella-Rondo’s.
But I said she couldn't convince me though she talked till she was blue in the face.
Yet as we hear the narrator’s version of the story, where she constantly thinks other people are in the wrong, we get the idea that she might be the one who’s wrong. In this case, the first person narration actually adds to the drama of the story, because we do not trust the narrator.