User blog comment:Sargenttacos115/Natsu and Gajeel age Theory/@comment-173.49.1.230-20140530041013

Time travel might be involved but I doubt that it was an accidental thing that only targeted the Dragon Slayers. In the Phantom Lord arc Gradinene and Igneel discuss the actions of Natsu after the battle with Gajeel. So the dragons are still very much aware of what is going on with their 'children?' and I doubt they can live as long as 400 years because of the corpse of the dragon underneath the Grand Mage Colosseum