It is well known that a matur child get mukallaf: it will need to perform acts of worship and it's actions are recorded.
But what in case of a child who first of all has the look of a higher age, but the mind of a child of lower age? The child's action differ without clear lines, from action of a person who can reason to those of a child that is still foolish in its actions. In other words is there a modern description of conditions of maturity?