User blog comment:CNBA3/Neinhart = Simon Theory?/@comment-1153699-20160211055931/@comment-1153699-20160211070831

I wasn't really being serious about the "Erza and Kagura are sisters" part. But as unlikely as it is, it's still not impossible. Almost nothing is in FT.

As for Neinhart, I also think him being Simon is ridiculous as hell since there's no way Simon could get that strong (if he's even alive that is). But I doubt Neinhart is just "another Spriggan". There's clearly more to him than that.

Seeing as we're nearing this series's end and still know pretty much nothing about Erza's family, I think Neinhart being her father (or brother) is definitely possible.