Mania.
-- Narration (N/A paragraph 1)

Importance: This one-word sentence is the very first sentence of the story. The sentence acts as a brief, broad description of the son's mental illness, thereby emphasizing the role of the son's illness in the overall narrative. The son's mania is later explored as a source of general pain and tension.

The love they had for Pete was long and winding, not without hidden turns, but without any real halts.
-- Narration (N/A paragraph 1)

Importance: This line of narration establishes the deep, consistent sense of love that both the woman and the son have for Pete. In contrast, Pete has apparently begun a slow but steady process of withdrawal from them following the worsening of the son's illness, thus creating the main tension of the story.

To me you always look so beautiful.
-- Pete (N/A paragraph 2)

Importance: This sentence is something that Pete used to often say to the woman. However, in the story, this quotation is presented as...