I think it depend on person to person. You can generalize everyone

. For some it make happen very early, few will use deodorants at 12 years. I think I started using it a young age, though I don't have a strong BO

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I like people who use deodorants. People who don't use it usually use it really makes a bad impression with all that body odor

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I think it's best to ask your children using a body deodorant at a young age, my eldest son will be 8 years old next month
I will ask him using it asap, but he is already fond of perfumes and fragrances. I am sure he will start using it soon

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