A family tree for the Ancient!John 'verse:
Now, the sad thing is I mostly had all of this figured out already in one of my story notebooks... I only had to look up Pictish/Gaelic names for Ianus' family after the Exodus, on Earth. (PS, I've Ianus setting up camp in Linne Mhoireibh, which is known as Moray Firth, Scotland in English... because with Carson being Scottish and O'Neill being of Gaelic orgin as well, I figured, if Ianus is the forefather of the ATA gene in Terrans in this 'verse, why not have him move there, thus making the gene more promient in people from that area due to interbreeding and whatnot among his descendents)
Anyway, as I understand this is a bit of a confusing picture, particularly with the Alteran naming conventions I've adopted, here's a bit of a primer and then the written-out version.
Atleran names have up to four parts: nomen, gens, cognomen, and dignitas. This roughly translates to first name, last name, nickname, and title. So if you were General Jonathan "Jack" O'Neill, the Alteran form of it would be Jonathan O'Neill Jack General. This is adapted from Latin naming conventions.
Dignitas on this family tree include: pastor (see fic), tribunus/tribuna (major/lieutenant colonel), legatus/legata (lieutenant colonel/full-bird colonel), navarchus/navarcha (ship's captain), magister (teacher/professor), and rector (dean of an instituion/head of R&D).
Iohannes Ianidus Licinus Pastor is John Sheppard in this 'verse. He is the son of Ianus Ishachidus Ianitos Rector (Janus) and Alianora Cado Trebal Legata.
Ianus was the only son of Beatrix Aona Nebriae Tribuna and Ishachus Ival Magister. During his exile on Earth, he married the Terran Mael Murie and had one son, Davidus Constantin (David Constantine), with her.
Davidus Constantin had four children: Constantin Iain (Constantine John), Iseabal Liusaidh (Eleanor Louise), Catriona Mael (Catherine Mael), and Iagen Daibhidh (Ianus David).
Constantin Iain had two children: Constantin Daibhidh (Constantine David), who would go on to be one of the direct male-line ancestors of Jack O'Neill, and Ealasid Seaonag (Elizabeth Joan), who would be the direct female-line ancestor of Carson Beckett.
Ishachus was the younger son of Davidus Ival Magister. Davidus Ival's other son is Elernus Ival Asuras Rector.
Elernus married his research assistant, Olethea Nydia. Their only child was Danielia Ival Helia Navarcha.
Alianora was the younger daughter of Constantina Cado Historica and Festus Alder Tribunus. Their other child was Catalina Cado Historica.
Festus was the younger son of Iohannes Alder Legatus and Ilaria Noval Pastor, who was the woman to pilot Atlantis from Terra to Lantea in 8343 BC. Their other child was Antonious Alder Navarchus.
Basically what this amounts to is that, by the end, everyone left on Atlantis towards the end of the war was related to each other. Very releated to each other. Ie, no one alive by that time was more than third cousins with anyone else. Granted, on Earth, everyone alive is fortieth cousins or less with everyone else, but still...
The upshot of all of this is, if you can read between the names, every major Ancient we encounter in SGA is on here, in one way or another.... and that I really, really need to get a life.
(PS, the dates on the tree couldn't be changed from BCE/CE in my family tree maker program. Assume for these purposes BCE means before Atlantis left Terra and CE means Aetaes Lanteae, ie, years after Atlantis landed on Lantea.)