Parents, can you share an observation of your child that led you to a surprising revelation about humans in general?

I couldn't post this on r/parenting. I've never had kids, and I don't plan to. Couldn't figure out where to post this. Anyway, what's a surprising revelation you've learned about humans just from observing your child's behavior?

I mean like, I've seen those videos where kids are scared of their shadow. Or that kid that kicked the ball and went to do thumbs up but he first had to do pointy index fingers, and consciously had to change them to thumbs. Stuff like that blows my mind, that the simplest things we take for granted, we all had learn those things once, the hard way.

Or maybe something like, observing your kid's coping mechanisms and how they relate to adults? I'm always curious, bonus question I guess, after raising children, do you find a new perspective on adult humans, that perhaps you become more forgiving of them, knowing we're all just children stumbling our way through life? Or maybe the opposite? Or not at all?

Or like, you have 3 kids and they all have different personalities, different triggers, different ways of dealing with problems... do you find that they retain those personalities into adulthood?

Sorry went a bit off the rails there. But as someone who will never have children, these are the kinds of things I'm sad to be missing out on. Anthropology lol.