I did know what you can get from a concussion. When I was 11 years old, I had a minor concussion. I got hit in the head and sat out for two weeks. I had a headache for a couple of days and then I went back to playing sports. I didn't know about the severity that it could lead to. I didn't know anything about mental health issues, losing out on school, and not having the social aspect that a teenager should. I knew some of the consequences but not to any extent.
On November 21st, 2018. See this statement in context.