Josephus implies that Ptolemy IV and V ruled as co-regents under Ptolemy III, "The Do-Gooder". After Ptolemy IV was murdered and Ptolemy V also was performing badly, Ptolemy III is depicted as personally traveling to Jerusalem to deal with matters. Only then does Josephus describe the rise of Joseph son of Tobias. Has Josephus botched this narrative? Could Ptolemy III still have been living and ruling at the same time as Ptolemy V? Was Ptolemy III preoccupied in Parthia for most of his reign (under the name Arsaces), and did he leave the rule of Egypt to his co-regents?
Recently I mentioned a Ptolemaic web site. It features a list of co-regencies, but does not consider any in the reign of Ptolemy III.
By the way, the author of this web site (affiliated with the Christian publishing house Tyndale) once wrote an amusing (albiet highly sarcastic) "review" of my researcb:
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