User blog comment:IamJakuhoRaikoben/Chapter 482: Vigor, Review./@comment-24102956-20160419153757/@comment-24102956-20160419223229

Well, the Spriggan 12 are composed of the extremely powerful and skilled Mages under Emperor Spriggan in Alakitasia and sometimes they are wary of each other's strength that either made them equals or at uneven terms of strength.

It's the only theory I got, man but sometimes it might either be right or wrong. Besides it might probably explain how did God Serena managed to obtain a seat among the Shields of Spriggan after his defection to Alvarez if Eileen hadn't left the continental superpower country and settled in Fiore to have a family with some good man and their daughter Erza.

Well anyone with that age appearing young-looking would invoke the trope Older Than They Look because good looks and everything about the person might be fooling the true age to the eyes of others.

Perhaps Neinhart was the man who had greatly respected Lady Eileen in the past for a good reason that would invoke in swearing an oath to protect her child and be at her side for redeeming himself maybe and might probably defect to Ishgar's side with the near entirety of his troops and Neinhart Squad following him even if Erza, Jellal and Kagura doesn't like him for what he is but they'll manage since he's needed to turn the tide of war back into their favor.