Right around the age of 10, there is a marked shift in a child's perspective. The world is no longer simply a wonderland of curiosities, but a popularity contest. Girls begin to wear makeup and form cliques, and boys become showmen, proving themselves with their fists. Think of Mean Girls or The Outsiders. In Lacan's terms, once we identify ourselves as "other" in the mirror stage, the beasts of jealousy and self-consciousness arise. This is a time in psychological terms in which children, going through their first major identity crisis, often begin to designate others into two categories: the in-Group and the outgroup.