You are correct, the person was on life support. But they grew and went through puberty like any other normal functioning human. (I believe the person was born brain dead, and the wealthy parents couldn't let go so they kept the person on life support at home).
Cells are living things by definition. So it is alive, though the body functions more like a tree than a mammal at that point. But a decentralized nervous system grew around the different vital organs.

You truly believe the semantics of the English language disproves the point? English and the way it defines "I" is greatly affected by things seperate from biological definitions (one being the spiritual concept of the "soul")
Also, there did exist languages in other cultures that did not have the same concept of "I" as the English language. Your counter-argument is very weak.