I've seen posts here on Sspot saying it's common and others saying it's not. Personally I know a few cousin marriages but most are 2 or 3 cousins aka same sub sub clan, most people I know though are married to people from the same clan (example two different Dhulbahante or Isaaq subclans). I know sometimes cousin marriage happens but it's WAY less common than in the Arab world or Pakistan. My parents are both daroods but from two different qabils who live far from each other, on my dad side many of the women my ancestors married are Hawiye so completely different clan