I am assuming that there was a topic on the subject of Tenchi's sibilings. This topic is a review. We do know that Tenchi has two siblings to date. Both are his sisters. The first sister who we know is Tennyo. She is eighty years old when she was first introduced.
The second sister is more of a mystery. Her name is Miyuki Kuramitsu. She is Tenchi's and Tennyo's older half sister . Information about Miyuki is very sketchy at the present time. According to Masaki K., Miyuki's and Tenchi's mother had an affair with a male member of the Kuramitsu family. The Kuramitsu family was opposed to the affair because Kiyone was from Earth. Kiyone became pregnant before ending the affair.
Kiyone was 248 years old when she died from old age. Tenchi is likely to have a few more siblings. One of his siblings being a brother. Since Miyuki's last name is Kuramitsu, she is definately related to Mihoshi.
Mihoshi's Great-Grandmother's name is Miyuki, too. I assumed that Miyuki was name after the older Miyuki Kuramitsu. It be funny that Mihoshi turns out to be Miyuki's younger half sister.
