It is okay for a 8 year old boy or boy of any age to wear just a diaper and shirt or diaper in public.
Last summer my neighbors 6 year old son was outside playing in the sprinkler wearing just his Pampers Baby dry size 7 diaper and shirt and he looked so cute.
Here's an 8 year old boy wearing just his diaper and diaper and shirt and a boy of around 7 or so wearing just his diaper shirt and shoes.
And here's also a picture of an 8 year old boy wearing just his diaper shirt and shoes in public.
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