Gender Roles

In our society, both gender and peer groups play a vital role in the developing child’s life.
Please talk about how gender roles influence the developing child, cognitively, physically, and social/emotionally. Is gender biological or is it influenced by society? Are people born gay? What about trans? What sources can you cite to defend your statements?
Peer groups, particularly in middle childhood and adolescence are often greatly influenced by and formed around gender. What is the importance of a peer group? How does being involved in one (or not) impact growth and development in all the domains? [Cognitive, physical, and social/emotional] What sources can you cite to defend your statements?