User blog comment:Ash9876/Fairy Tail Review -- Larcade's Involvement/@comment-3045936-20161206215215

My thinking is Larcade is truly Zeref and Mavis's son. But is their child formed from their Love mixed with their great Magic Power. Thus manifesting him as the embodiment of their love from their power. I wouldn't be surprised if he was created from a side affect of Anhkseram's curse.