Student or Learner
When reflecting on events in my life that have forever changed me, there is one that is highlighted above all the rest; a winter night from 2004 when I found out I was going to be a sister. Let me begin by telling you that I spent ten, long years as an only child. By that point, all my hope of ever having a sibling was long lost and my aspirations had shifted to the attainment of a puppy. But that night, without any hesitation in his voice, my father announced to me that my mother was pregnant. I remember not knowing what to feel; immediately it was disbelief, which transformed into shock, which grew into elation. However, that elation was short-lived as my mother was hospitalized just a month after learning the news. I was too young to understand the full extent of what was happening, but my family was sent into a whirlwind of stress and worry; both for my mother's life, and for the life of my yet unborn baby sister.
How many words are you permitted for your essay?
Your opening sentence bothers me. It needs better vocabulary and structure. The rest of the paragraph is good.
When you say: "When reflecting on events....etc," are you telling us that the one single event that forever changed your life was when you learned that you were going to be a sister? The path that the rest of the paragraph seems to follow does not make me feel that learning of your mother's pregnancy was going to be your life shaping event. I get the feeling that there is an event further down the road that will turn out to be the one that changes your life forever. If I'm wrong, then just concentrate on the structure and vocabulary of the sentence. Highlight isn't a good word. When you reflect, you generally call things to mind - not highlight. As for the rest of the paragraph, here are some suggestions:
- no comma between ten and long
- had shifted to just getting a puppy ("to the attainment of" sound pompous)
- hospitalized just a month later (you used too many words)
- and for the life of my baby sister (we know she's unborn, it's been only 30 days)
Most application essays have strict limits on the number of words you may use. Write economically but passionately.