This reminded me of something I learned about years ago. There is a serious study of the sociology and psychology of group photos - barbecues, reunions, Christmases, weddings - and the meaning behind the grouping and stances of people. It's really fascinating to see the tiny clues behind where people stand in relation to one another, and how they position themselves within a group, along with what their individual body language is saying. You can learn a lot about people.