We are dealing with closely related, even highly inbred family members, so I don't want to make too much of this exercise. Also, the bust considered to be that of Josephus was not marked, so we don't know for sure that it was actually his.
Ron, as usual the impossible is no obstacle for you. So, Caligula staged his own death and reclaimed the throne later as Nerva? Caligula would have been somewhat older than Nerva I think. Yet, we don't know exactly when Nerva was born and it does now seem certain that the deaths of Caligula's two older brothers were faked. Turn about was fair play? At issue would be whether or not dropping back fifteen yards and punting was an option for a prince who made it all the way to the top. Probably not, but hey, there's a first for everything under the sun.
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