User blog comment:LordLuminous/Silver being Deliora = Impossible? Theory/@comment-24734283-20140705195126/@comment-83.255.195.39-20140706003021

It could just be that Silver knows who Natsu is and knows about his releationship with Gray but have never meet him in person. Silver maybe has spied on Gray and his life in the Fairy Tail Guild for a while or maybe Igneel, Zeref or somebody else told him about Natsu.