User blog comment:FairyRaven/Fairy Tail Chapter 448: Fight the Power! Review and Commentary/@comment-24546844-20150817211613/@comment-26389992-20150818004037

good theory, what I takeaway is that this obviously occurred between the 10 year gap when FT was created and Mavis died... I wanna say Zeref tried to save Mavis by storing her real body in Fairy Heart but there's so much we don't know... can't fucking wait till next chapter yo!