Don't let your child or grandchild end up like K's husband:
I remember using butter knives to make PB&J from age 3 at the oldest, and sharper knives, with supervision, not long after that. My dad (the cook in our house) was sure to teach me what knife to use for what job—if you try cutting an apple with a knife that’s barely sharper than a butter knife, it’ll slide and you’re much more likely to cut yourself. A good, sharp serrated knife is actually much safer, because it goes where you want it to.
I do remember slipping and cutting a finger once or twice, but nothing scarring– in either sense of the word. And now I’m a confident cook.
Contrast this with my husband’s upbringing– “Don’t come in the kitchen! You’ll burn yourself! You’ll cut yourself! Don’t touch that!” He ended up being terrified of the kitchen and having no confidence in his ability to figure anything out, and I had to teach him how to use a can opener when he was in his mid-20s.