What age to teach a boy to kill a fish?

[Cheechat]

Hi all - My oldest is 4 now and raring to fish. His mother and I debate this topic often. We want him to understand that things must die in order for us to live but when is he old enough to see his dad knock a fish out with a hammer handle and then start filleting? How do you all knock out/kill a fish to clean it? How old is old enough to see the process? I think I was around 8 or 9 when my father showed me how to chop off a trout's head and then stick the knife point in and run it up and then clean the guts out. I remember it was kind of graphic to me but I ate that trout I caught with my dad and it was tasty. Thanks for your help.
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