You cannot tell a child that he is bad. This creates complexes and gives a feeling of being unloved. A child may do something bad and this needs to be conveyed to him somehow. The best way to do this is through fairy tales or stories. The child will draw the parallel himself. And he himself will understand that he is wrong. Especially if you later discuss this fairy tale with him. A fairy tale for children from 3 to 8 years old and adults up to 99 years old.