User blog comment:Omega natsu2/Chapter 368: The Third Seal, Predictions./@comment-5598380-20140120235402/@comment-7418318-20140121092620

How can you say that Crawford and Zero have no similarities in their looks when all you can see of Crawfords face is eyes and beard?

If he slimmed down and shaved, maybe they'd look alike. And even if not that would still proof nothing, since Zero might have inherited his appearance from his mother's side.

But juding relationship on shared magic doesn't make much sense either. As chairman Crawford most likely had access to pretty much any teaching material there is and also the discoveries of the bureau of magical research, so it'd be easy for him to learn Archive Magic.