I just found this on a different post. It is all making since now.
DiMera's Rise Again!
It has recently been revealed by incoming head writer Hogan Sheffer, that EJ is in fact a DiMera! Most if not all of us suspected, putting two and two together; English accent, Susan's baby was named Elvis John, that child was Stefano's prodigy; hence EJ was likely to be Stefano's child. But wait! There is more news, but I can't tell you hear it might ruin the surprise for some, so if you really want to know go read the Coming and Goings page. ;-)