[petercooper]

I imagine many people find it tricky enough to live with their own kin, but we have lots of mechanisms to generally make it work that don't really work with broader groups of people (e.g. marriage, societal expectations, judgment by broader family/in-laws, intimate relationships). It doesn't sound like the people in the article live in the very same living space, but there's a fine line between "close-knit community" and "living together."

[skydhash]

This very much. Harmonious groups only works when there's a clear hierarchy and group pressure to do well (basically a miniature society). And even then you have bad apples. Even in a single family, you can have conflicts. Imagine scaling it to several.