Answer:
In their teenage years.
Explanation:
The moral development theory was proposed by Kohl-berg. These theories have three-level and six stages. The teenage occurs in the conventional level and third stage. At this level and in this stage, teens develop a moral conscience. At this stage, teens believed that a person behaves in a manner that is adapted by families and social norms or behaves in a good manner. It indicates that behave in a manner such as love, empathy, and concern about others.
Thus here in the above contest that Kohl-berg's theory of moral development about the concern of others in teenagers occurs in the second level and third stage. Teen starts to think about the concern of others and behave in a good manner.