On the main site we have [minor]
Use this tag for questions related to the law for minors, i.e. persons who have not reached the age of majority (usually 16, 18, or 21 years).
and [juvenile-law], which has no usage guidance.
I am not sure whether there is a useful distinction that could be drawn. Perhaps juvenile-law should be a synonym, but if not, it should certainly have usage guidance.
(There is also [children], typically for use in family law context, and [child] which is deprecated, so confusion there is unlikely if used properly. I am doing some work cleaning up [child] at the moment.)