My point, above, is that this isn't necessarily a good abstraction. The edges could be directed (A considers B a friend, B does not consider A a friend). The gr

My point, above, is that this isn't necessarily a good abstraction. The edges could be directed (A considers B a friend, B does not consider A a friend). The graph may not actually be complete (maybe absence of friendship is different from non-friendship), and so on. So yes, if kids' friendships form a complete undirected graph, then sure, your result is not at all surprising. But maybe they don't.