I have two sons and two stepsons. The oldest is 32, the youngest is 16. Although none of them bowl seriously at this point, they all went through juniors, and all have pretty good fundamentals.
I expect that a couple of them will pick it up at some point in their lives.
No - I wouldn't do anything differently now if it were my grandchildren. (and I don't have any of those, yet.)
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If winning isn't important,
why do they keep score?
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Vince Lombardi