User blog comment:TheCarrotSaysYumYum/Dragons, People and Demons.../@comment-4223231-20120721152628/@comment-5201441-20120723090618

Maybe this sending to other dimension thing is just for a while, then they come back. If so, maybe there was one time that the dragons were sent to Edolas. That's why they know about them. But the truth is: I have no idea! :)