User blog comment:PUNCHURPREGNANT/Gray and Silver Predictions/@comment-50.171.74.14-20140310194203/@comment-134.76.38.67-20140311140753

I think that Natsu and the other Dragon slayers may be time travellers from the time of the dragons, and they lost all memomry about that, so they only remember the day they arrive to earthland. There is no explanation about why gajeel and Natsu couldn't pass the rune barrier of Freed, so they are older than 80 years, and if zeref was asleep for 400 years, why Zeref would remember him ant tell him he has grown up? so many questions and not so many answers yet... And I think if the 9 Demons gate were all created by zeref, they are about 400 yo as well.