[crooked-v]

If you really want to stress-test an arbitrary family tree documenter, try putting the X-Men in it.

http://img13.deviantart.net/4a05/i/2011/253/c/b/x_men_family... (and that's just the tip of the iceberg!)

Real family tress don't have to worry about time travel or cloning, of course, but that crazy stuff does actually serve as a reasonably good proxy of some of the strangest family trees out there (medieval European nobility, extended families with multiple divorces and remarryings, etc).