User blog comment:JAlbor/Wikia at E3 2012/@comment-4681429-20120523203047/@comment-1153722-20120524203452

Just so you know, it is never stated in the actual games, books or whatever (yes, I know it's on the back of the Revelations box and in the Encyclopedia which are both sloppy errors) that Altaïr and Ezio are related, not even in AC2.