Thought challenge for my friends

Aristotle drew a distinction between 'essential' and 'accidental' properties. Essential properties are qualities that something must have to be what it is, and accidental properties are attributes that a thing happens to have but that it could lack.

One's rationality, according to Aristotle, is an essential property of being human. One's hair color, by contrast, is merely accidental. Hair color is how they are; it's not essential to who they are. A chair is essentially something you can sit on, be it accidentally made of wood, metal, or plastic.

So, my friends, what are essential properties that make you who you are? What are qualities others consider to be essential in you, but you feel are merely accidental?