Sigurd married Deirdre, and they had Seliph together. Then Sigurd got cucked by Arvis, and Arvis married Deirdre, which makes Arvis Seliph's stepfather. But Arvis is also Seliph's half-uncle, which makes all of Arvis' kids Seliph's cousins (I think half-cousins would make more sense, but whatever). But Julius and Julia, who are also Deirdre's kids, would then make them Seliph's half-siblings since they share the same mother. So are Julius and Julia Seliph's (half?) cousins or his half-siblings? Or would it be both? It's confusing.
But wait, would that mean Leif and Altena would be the niece and nephew of Arvis by law since they're Seliph's cousins and Seliph's mother is Deirdre and that makes Leif and Altena Deirdre's niece and nephew, but since Deirdre is married to Arvis, that would make Leif and Altena Arvis' niece and nephew by law?
Also, would Azel be Seliph's quarter-uncle?
Oh yeah, Seliph and Saias are (half?) cousins too.
I guess I shouldn't have to say this, but feel free to joke around about how complicated this family is, because holy shit.