I thought about giving some food for thoughts for the first time anime viewers.
This is the character table from the official umineko anime site
http://umineko.tv/web/main/character/index.html
So everything contained there is meant to be available to anime viewers, however most of you probably do not understand japanese, so I'll try to explain what is it written there.
Upper left square: Eldest brother's family:
Ranked 2nd -
Eldest son - Krauss Ushiromiya
Ranked 10th - Natsuhi Ushiromiya
Ranked 6th - Jessica Ushiromiya
Upper right square: Eldest sister's family:
Ranked 11th - Hideyoshi Ushiromiya
Ranked 3rd -
Eldest daughter - Eva Ushiromiya
Ranked 7th - George Ushiromiya
Center left:
Attending physician - Nanjo
Center:
Ranked 1st - Kinzo Ushiromiya
Lower left square: Second brother's family:
Ranked 4th -
Second son - Rudolf Ushiromiya
Asumu (died six years before) <- that's Rudolf's first wife
Ranked 12th - Kyrie Ushiromiya <- second wife
Ranked 8th - Battler Ushiromiya <- the graphic shows that Battler was born from Rudolf and Asumu
Child <- There's no other info on this mysterious "child", but the graphic shows it was born from Rudolf and Kyrie
Lower right square: Second sister's family:
Husband <- I wonder why they used the kanji of "husband", afaik Rosa never married. There is no info about this mysterious man, the only reason to suppose his existence is the fact that Rosa couldn't have procreated alone.
Ranked 5th -
Second daughter - Rosa Ushiromiya
Ranked 9th - Maria Ushiromiya
Family servants:
Head servant: Genji
Servant: Shannon
Servant: Kanon
Servant: Gohda
Servant: Kumasawa
On the lower left corner we have the two witches known so far:
Beatrice and Bernkastel
to the right from there
the seven sisters of Purgatory:
Eldest sister - Lucifer <- pride
Second sister - Leviathan <- envy
Third sister - Satan <- wrath
Fourth sister - Belphegor <- sloth
Fifth sister - Mammon <- greed
Sixth sister - Beelzebub <- Gluttony
Seventh sister - Asmodeus <- Lust
As you can see there are a few info here that were never disclosed in the anime.
First off you may wonder what is this rank system. The character table shows every Ushiromiya's rank, but neither the site nor the anime explain why. The novel did at this point, but for that you'll have to read the thing under "spoiler" at the bottom of my post. Anyway you might want to take a closer look at how the family members are seated during lunch and dinner:
Another thing that in the anime wasn't mentioned but it is clearly shown here is the complex Battler's family situation. Asumu was never mentioned in the anime, but she's mentioned here. She was Rudolf's first wife and Battler's mother.
Kyrie is the second wife. You can see here that Kyrie and Rudolf had a child.
I guess you are completely clueless as to what's this child's name and sex and why you don't see this child at the family conference. This was explained in the novel since the beginning, but it appears that Studio Deen thinks it is better for the anime viewers to not know for now.
If you want to know anyway, see below under "spoiler tag".
Another thing that the anime hasn't covered yet is the full list of the seven sister's names. This character table also explains the age order.
Now for those who wants to know more.
What is under the spoiler tag below is only stuff that was uncovered in the first Episode (anime ep1 to ep5), however as per rules established by the mods, I still put it under spoiler tag because that's info not included in the anime. So it is your call whether you want to read this or not.
Spoiler for Rank system:
The rank system in the ushiromiya's family is quite peculiar. The first condition that must be met to be included in the rank system is to be an "Ushiromiya".
This sounds kinda obvious, but you need to think about how surnames work in Japan. Once someone marries he doesn't just marries with a man/woman, he marries into a family. Which means Eva was supposed to marry into another family and therefore she would have lost the Ushiromiya surname and any right to be listed in the Ushiromiya family rank. However in Japan under certain circumstances the man can marry into the woman's family. Since Hideyoshi after the war had practically lost all of his relatives, he gladly married into Eva's family, thus becoming an Ushiromiya himself. It is said that Kinzo accepted this because at the time Krauss and Natsuhi still didn't have any heir, and in the worst case scenario Eva and Hideyoshi's son would become the next head.
In Rosa's case, she never married. Therefore she's still an Ushiromiya, and so is her daughter. Nothing is known about Rosa's father.
The most peculiar characteristic of the Ushiromiya's family rank is: "blood" above all.
This is why the cousins are ranked higher than the four brother's spouses. Natsuhi for example is the wife of Krauss which is ranked 2nd and the next head after Kinzo. However Natsuhi's rank is lower than Maria's which is a 9 year old child.
That apart the rank order follow the age order of the four brothers: Krauss, Eva, Rudolf, Rosa.
Then on second tier you have the order of the cousins which still follow the age order of the four siblings (i.e. while George is the oldest cousin, he's still second to Jessica because he's the son of the second sibling): Jessica, George, Battler, Maria.
Last you have the spouse tier which still follow the age order of the four siblings (well.. three since Rosa is unmarried): Natsuhi, Hideyoshi, Kyrie.
What about Kyrie's child now? Logically speaking it should be ranked 9th, after Battler and before Maria. But this is mere speculation because the novel never cared to explain.
Anyway as you have seen, only blood relatives are allowed to bear the family crest on their clothes, so Natsuhi, Hideyoshi and Kyrie are excluded. Asumu was probably like that when she was still alive.
The rank order is reflected on the seat position at the dining table. Kinzo is supposed to stay at the head of the table, then from left to right, everyone is seated based on their rank, so:
Krauss__________Eva
Rudolf__________Rosa
Jessica_________George
Battler_________Maria
Natsuhi_________Hideyoshi
Kyrie___________Nanjo
Why Nanjo is there? Because that was the last seat available. He isn't really supposed to be in the Ushiromiya rank. There was a controversial sentence in the novel said by Battler. Battler claimed that that seat was supposed to be prepared for Rosa's husband. However that was probably a speculative thinking since Rosa never married and no one is supposed to know who was that man (except Rosa herself).