Below, you'll see any text that was highlighted with comments from the reviewer.
The title tied with the one-word sentence in the beginning instantly creates an ominous mood that wants the reader to know what happened on "That Night".
It is clear that some traumatic event occurred based on the thoughts and actions on the character. The last couple of sentences also guides the reader of the general idea of what happened, yet it still leaves room for speculation (how did the sister die?).
Details are great as well as the line of thought portrayed :) I especially liked your diction or word choice!
Great work! I can't wait to see you become a stronger writer--you're already walking on path to get you there!