The Joseph who was charged with monitoring Mariamne in Herod's absence was probably Herod's uncle named Joseph, at least according to the book "Life and Times of Herod the Great". I think the Jewish Encyclopedia may be in error about this Joseph being the brother-in-law of Herod. (I said father-in-law in my previous post, oops.)
Also, the following genealogy mentioned in a previous email has a different lineage for the Joseph who was husband of Olympias. I thought that this Joseph was the son of Herod's brother named Joseph but it makes him son of Herod's uncle Joseph.
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