Kishuku is Tamahome, a Suzaku seishi and protector of Miaka (Suzaku no Miko). He's 17 and has the symbol of the ogre (scary) on his forehead. His power is martial arts in general. He's obsessed with money (this kind of rubbed off onto Chuei too) and does anything for it. It's for a good cause though; it was to support his family. He was the one who raised the youngest, Yuiren. (their mother died giving birth to her.) She was his favorite. Tamahome falls in love with Suzaku no Miko and later marries her. His reincarnation into the real world is Taka.
Gyokuran
She's the third child after Chuei. (and my second favorite) She helps around the house and doesn't say much. She isn't seen often. However, in the manga, she was the one who said the lines Yuiren is most famous for:
"Are you my brother's wife, miss?"
Hotohori: "No, I am a man."
"But you're so beautiful!"
Shunkei
Shunkei is the fourth child. He's the youngest boy, and pretty kawaii too. ^_^. Not much is known about him, as he gets even less screen time than Gyokuran.
Yuiren
The youngest child, Yuiren seems to be the source of all things cute and innocent on the show. Her mother died giving birth to her, and she was pretty much raised by Tamahome (she's his favorite.) She always says exactly what's on her mind. She called Miaka Tamahome's wife and told Hotohori he was too beautiful to be a man (which pleases him....). When Tamahome came home after Suboshi had killed the others, Yuiren was still clinging to life. She asked him to stay with them forever, and then she died in his arms. (if this doesn't make you cry, I don't know what will.)
The Sou Father Guy
He's the father of all the above mentioned kids. He was very ill until Mitsukake healed him (which wasn't too useful, 'cause he died about a week later anyway). He is very supportive of his children. In Tamahome's dream near the end of the series, he's the one that convinces him to go and fight.
The Sou Mother
Um... she died five years ago. When Yuiren was born. So... nothing is known about her. She doesn't appear in the series. *awkward silence* She's dead! She doesn't live anymore! *more awkward silence*
-_-;;