I'm not a believer, but I'm willing to bet there was a person named Jesus who had relatives and that all were buried somewhere.
As a lover of history and archeological digs that confirm written tales of the past, whether Greek, Latin, or Hebrew--or Sanskrit for that matter, I love to these types of finds.
I'd like to recommend a book I read recently called "The Jesus Dynasty" by a Biblical scholar and archeologist that pulls together a lot of the recorded history of Jesus in the various books of the Bible and has some pretty good theories on his birth, his brothers, several possible tombs and ossuaries and the operation of the Church after the crucifixion. For a non-believer to recommend it should tell you a lot.
Go to this url for some really interesting excerpts.
http://www.jesusdynasty.com/Exerpts-from-James-Tabors-Jesus-Dynasty.html