A container is where individual objects are linked as one object, so when you create the base, it creates everything else too. Then when you reference the objects it knows automatically which base or head is linked to it because they are in a container. Only possible problem is if you destroy one of the objects then they are all destroyed. Even if it were to be unpredictable I would go with several animations that you can choose at random, it has to be easier than trying to animate these connected sprites.