Board Thread:General Discussion/@comment-5674726-20150813192004/@comment-5674726-20151221211651

Remember that interview comments aren't canon. Canon is only what you see on the show, which leaves the question open. It is also entirely possible that the information is out of date; this interview took place in Season One, at a time when they were showing enough flirtation between Morgana and Arthur to make it sick if they planned them as siblings from Day One.