The infobox in this article lists Arthur Weasley and his two brothers as Cedrella's sons. Although I think there's reasonable evidence to support this relationship, it hasn't been directly confirmed anywhere, at least to my knowledge. I thus question whether this and other articles should treat Septimus and Cedrella as Arthur's parents.
Sirius Black states in Ch. 6 of Order of the Phoenix that Arthur Weasley was "something like [his] second cousin once removed." According to an essay on The Lexicon, if Arthur was Cedrella's son, then he and Sirius would indeed be second cousins once removed. ★ Starstuff (Owl me!) 14:47, 17 January 2009 (UTC)
- I tend to think it's a bit too coincidental that Septimus and Cedrella being Arthur's parents would make him and Sirius second cousins once removed if Rowling didn't intend it. Also, as that essay correctly states, if Arthur were some other relative of Septimus's (his brother or nephew or cousin), then he would only be Sirius's relative by marriage. Since Sirius made a distinction with Molly being his cousin by marriage, then it's a reasonable assumption to think he meant that Arthur was his relative by blood. It's also possible that another Weasley man married a Black woman, but none appear on the family tree and we know most of Sirius's relatives, since both his parents were Blacks. It's possible that a Weasley married a relative of one of Sirius's grandmothers, though, and that this is how he and Arthur are related. However, since Sirius is discussing his relation to Arthur while looking at the Black family tree and since a Weasley specifically appears on the family tree precisely where it would make Arthur his second cousin once removed, I find this unlikely.
- However, you're right in that it's never been confirmed. Maybe this should be mentioned in Behind the scenes sections, or in a footnote, in the articles in which it appears? Oread 16:33, 17 January 2009 (UTC)
- If Arthur is indeed Cedrella's son, then I believe he's the second cousin of both Orion and Walburga, making him a second cousin once removed to Arthur twice over. My working knowledge of geneaology is pretty poor, though, so I could be wrong. But, if I'm right, I think that JKR may have lined things up on both sides of Sirius' family tree deliberately. Alignment on only one side of Sirius' family (e.g., his father's) would be easier to dismiss as an unintentional fluke.
- I agree that we should probably post an explanation of how we worked out that Septimus and Cedrella are Arthur's parents in the footnotes. That's the general rule for logical inferences around here, e.g., Victoire Weasley's birth year, Dumbledore's birth season, Edgar Bones' death year. ★ Starstuff (Owl me!) 13:47, 24 January 2009 (UTC)
- I've studied geneaology a bit, and you're right; Arthur would be a second cousin to both Orion and Walburga (which would actually make him a double second cousin once removed of Sirius's, since they are both cross cousins and parallel cousins). I'll add a footnote explaining this and citing the Lexicon essay. Oread 19:34, 24 January 2009 (UTC)