Yeah, I was super short on serotonin but no one would of ever called me an old soul as a child. My ADHD keeps me running my mouth and being super irritating with people around. I only get quiet and reflect on my own mortality and pointlessness of all life once they walk away and I'm left with my own loud constant inner monologue.
Those of use blessed with the loud, fast constant sadness. We wish we could be called an old soul. RIP Robin Williams.