Just to augment my reply with a more personal and positive note on toughness. As a kid I was super active, doing lots of physical sports and training very hard.

Just to augment my reply with a more personal and positive note on toughness. As a kid I was super active, doing lots of physical sports and training very hard. By the time I was 18 I had that reckless abandon and confidence that only an 18 year old can have - that feeling of invincibility and that belief that anything is possible. Fast forward 10 years later after years of working super hard and not doing much exercise and accruing postural issues, I went skiing and felt very vulnerable and mortal - a stark shift from the me of 10 years prior! When I hit my 30s I made reacquiring that fitness again and started exercising super hard. Like 10-15 hours a week of intense physical training. To my surprise, I actually started to feel almost like an 18 year old again. I couldn't believe my subconscious outlook on life could be so malleable. What does this have to do with hitting kids and toughness? I've digressed a bit - I guess having some of that stoic grit is worth developing in children but I am undecided whether hitting children builds it in them.