This is something I found on the Tenchi Muyo! Ryoohki! page. A very informative page that I recommend checking out! Normally I don't believe in simply putting out something someone else has done, but I found this to clear things up a LOT for me. So I'm giving credit where credit is due, this is just a slightly more dressed up version of what is on the aforesaid page.
You may also notice that there isn't a whole lot of forking going on in this tree. Jurians commonly marry their relatives.... which is far more kinky.... I mean, wide spread than I origonally thought. Strait lines indicate good'ol fashion procreation. Dotted lines indicate unknown family branching. Broken lines indicate cheating (ie - genetic manipulation).