It's just that children want to flaunt their personality.
We should solve problems, not people with problems, so don't educate children through punishment.
Children must be a bad person to look at this correctly, not because of tattoos. There is no relationship between the two.
However, as a student, tattoos do bring him some negative effects, such as being misunderstood by people around him, affecting his future career choices (unable to join the army, enter military schools, enter civil servants and so on). , regardless of foreign countries, at least not at home).
Tell him the bad things and let him choose for himself. After all, life is his own, and he is also responsible for his own choices.
It would be better if the child could cooperate to wash it off. If you don't want to, don't force it. Otherwise, the negative impact on children is far greater than tattoos.