https://bugzilla.wikimedia.org/show_bug.cgi?id=73534
--- Comment #3 from John Mark Vandenberg jayvdb@gmail.com --- (In reply to Fabian from comment #2)
Well in the case of vikidia it assumes that the language code 'de' is a part of the family, but the Special:Interwiki page reveals that it's actually another wiki (http://grundschulwiki.zum.de/wiki/Hauptseite , although I don't know if they are affiliated): http://en.vikidia.org/wiki/Special:Interwiki
They are affiliated.
Wowwiki is the same: the 'family' is split across several domains - see our family file for wowwiki.