Terrible 2’s?? ADHD???

This is not a TTC post.. I hope that’s okay... wasn’t sure where to post this but need some support/advice.

I got the dreaded note from daycare that said my son had a hard time listening and following directions. I know it’s par for the course for a 2 1/2 yr old but my brother grew up with severe ADHD and it ruined his life. He was made fun of, started hanging out with the wrong people and long story short, now he’s a heroin addict. My mother keeps saying things about my son like “that’s how your brother was” and it’s freaking me out! Trying not to over think it, but can anyone else relate?? Is this normal?