User blog comment:Stone Roger/Natsu and Zeref have somekind of relation?/@comment-89.121.219.122-20130703151857/@comment-110.175.61.178-20130805071847

I agree. I recall reading awhile back that Natsu was around on the DCW and he was forced to fight Zeref or something like that. He probably was his dad as some of you people guessed and he was around for 400 years ( that's why he couldn't escape during the battle of fairy tail) and Zeref could have made Natsu's scarf ( that's probably why it only protected natsu from Zeref's attack) This is just my theory