It's funny you mention that about Dorian, Silver/, because of how established adoption is in Roman society, I'm still not sure what was going on with that plot.
Originally Posted by Silver/
If DA was not so Christian, Dorian raising another child someone of his bloodline had wouldn't be so problematic... nor would having a child without direct sex (and marriage). Even a relationship next to that marriage.
The crux of Dorian's plot isn't just about continuing the family lineage in the sense of inheritence and what have you, and it's not really a religious issue either. It's more about continuing to provide a linneage of powerful mages. Tevinter Magisters are expected to marry and have children in part to keep up a pedigree of powerful mages. Adopting the unwanted child of some cousin wouldn't really help with continuing the magical bloodline. It would effectively mean Dorian is putting an end to generations of breeding partially aimed at producing a superior magical bloodline.