User blog comment:FairyRaven/Fairy Tail Chapter 314: Erza vs. Kagura, Review and Commentary/@comment-58.110.34.148-20130116112854

Just realised how zeref knows natsu. Natsu and the others are going to the past to kill that dragon right so i think thats how zeref knows natsu because they fight in the past. That might also be how natsu 'finds' igneil as a child.

I'm just saying from my point of view.