During what period does the peer group become a major influence, for good and bad?

During adolescence

Explanation:

A peer group is a group of people who have similar interests, age, background, or social status. Peer groups influence a person during their entire life, but their impact is the most important during adolescence. Adolescents tend to spend less time with their parents, whose influence is the greatest during childhood, and spend more time with their peers. This is especially noticeable in the case of those who are not close or have many conflicts with their parents. Such individuals seek support elsewhere, usually turning to their peers. Most adolescents in this situation do not carefully choose what kind of group they join. If they are accepted, it does not matter if the group's influence is good or bad. Gangs are a common example of a peer group characterized by negative or even illegal activities.