"nursing them back to health" - Princeton Summers

The majority of my last two summer's were spent at my mother's and grandfather's bedsides, nursing them back to health. I administered their medication, cooked their meals, cleaned up after them, and most importantly talked to them. Knowing what life without a home is, I dedicated many of my Saturdays volunteering on Habitat for Humanity builds. I also pioneered a program at a local nursing home that helped elderly residents use modern technologies to reconnect with family members who, in many cases lived thousands of miles away. During a few brief days where my responsibilities allowed me some leisure time, I took the opportunity to visit Princeton to decide if it was the place I wanted to spend the next four years of my life.

Your writing is excellent, but what's the character limit?

"family members who, in many cases lived thousands of miles away."
I'm not sure whether there should be a comma there. if you decide to stick one in, you should have another one after "cases."

Apart from that, it is great.

i changed the essay and submitted it. Thank you so much.