I read on uesp a while back that at a certain point(?) in the Dawnguard questline, it becomes possible to have Serana plus one other follower accompany you for the rest of the game if you already had a follower with you when Serana joins the party. So I'm wondering if this is still accurate? And I'm also wondering, at which point in the questline it becomes possible? Any input is much appreciated. Thanks.