Personalities are complex things. They are formed from an interesting mix of experiences and genetics. They also change as people get older and experience new things.
However, everyone has a default personality that they will fall back on in a moments notice. No matter how a person changes or grows, this “default personality” will always be a part of you.
If you stop and think a bit, you will know this to be true. There is always a least one aspect of your personality that has stayed with you over the years. This could be compassion, ambition, or consideration. It may even be something else completely different.