Instead of going on Anteiku's side of the enzyme pills, I just thought of what I would do regarding Sora's family history. Enjoy!
So a look at Sora's family history (His ghoul family history):
Mother: Yoruko 'Yo' Chao née Minami, 1/8th ghoul. Video game fanatic all the way back to when they were first coming out. Was able to get a chance to look at Kingdom Hearts back when it was in its early conceptual stage, which was where she met Sora's father, another video game fanatic. Also how Sora ended up getting his name. Poor kid. Also a fantastic gambler.
Grandfather: Samuel Minami, Yo's father. 1/4th ghoul, first of the family to be able to eat human food without adverse side effects. However, this came at the apparent cost of being unable to access kakuhou/kagune. Able to eat human meat like other ghouls, but didn't get as much nutrition out of it as his father. Managed to convince his wife to allow him to give their child a Japanese name in order to preserve what was left of his Japanese pride.
Great-grandfather: Katsuro Minami, father to Samuel Minami, one-eyed ghoul. One of the first one-eyed ghouls in existence. He grudgingly allowed his wife Janna to give their child an English name after seeing how another Japanese child was mocked by his schoolmates for his 'funny' name.
Great-great grandfather: Masashi Minami, the original member of the family from which the family inherited their ghoul blood. Had a sibling that came with him over to the United States from Japan, direct ancestor to the ghoul side of Sora's family. Married a human and indirectly discovered how half-ghouls could be born when Katsuro was born through his wife's dedication to family.
Unlike their more human side of the family, the ghoul side of the family fully embraced American names and culture, being less stubborn about the whole thing than the human side.
Andy Minami: Sora's best friend. He and Sora did almost everything together as children, often working together to prank their not-so-amused parents. They even developed their own secret code to communicate without other people knowing. Easily the smartest kids in their family growing up. Andy is two years older than Sora, also goes to MIT, and is somewhat miffed that his cousin gets his own personal research lab while he has to share with someone. To be fair, he's also an exercise nut, so that puts him lower on the priority list.
Richie Minami: Andy's brother, younger than him by about five years. Academically speaking, he's about average, and has to rely quite frequently Sora or Andy to teach him the schoolwork. Occasionally helps Sora or Andy prank the other. Has questionable tastes in music, according to Sora.
Lily Brown: The youngest member on both sides of the family, Sora adores her to no end, to the point that he is willing to spoil her and give her pretty much anything she asks for. Thankfully enough, the rest of the family is more than willing to teach Lily her manners so she doesn't get spoiled.
Deborah 'Deb' Minami née Brown: Andy and Richie's mother and Lily's aunt, both through the fact that Lily's mother Jessica is her sister-in-law and the fact that her brother Robert married Jessica. It's kinda weird.
James Minami: Andy and Richie's father and, obviously enough, husband to Deb. Out of all the members of the family, he is the most likely to lose a bet. Although that's mainly because he always bets against Yo and Yo only bets when she knows for sure that she'll win the bet.
Jessica Brown née Minami: In a funny twist of names, Jessica and Deb have easily the funniest names out of everyone, mainly because there's so many things connecting them. She would have had to take care of Lily by herself, except everyone else in the family pitched in to help raise her.
Robert Brown: Lily's father. He died about a year after Lily was born keeping a ghoul safe from the CCG. Not much else to say here. A great man who always protected the weak. It was what eventually led to his death.
Obviously enough, there's the family that's still in Japan, although most of them were wiped out, with Riku being the only survivor. However, some of the family is still known.
Riku Minami: The last survivor of the Minami family in Japan. The family lived in Tokyo for the longest time before his aunt Uruka was killed when he was one year old. The family moved over to Kyoto, but was traced by the CCG and killed, with Riku only surviving because the CCG didn't realize that there was another member of the family and Andy helped him escape. Riku was eventually found by Aogiri tree and recruited into their ranks.
Uruka Minami: The reason the family moved to Kyoto, she was a high school student when she was killed by Kishou Arima, an investigator for the CCG. Circumstances regarding her appearance at the school in question led the CCG to believe that there was a family involved, which in turn led to the investigation of potential ghoul families that were in the area. Eventually, they were tracked down to Kyoto where all of them were killed except Riku. Put simply, she fucked up and got the rest of the family killed.
So yeah, that's some basic details as to Sora's family tree. I got inspired to write this while I was working on Chapter 21 of Reaching Out. Oh, and Uruka Minami is the same Minami from Tokyo Ghoul JACK. Thought that would be fun to put in.