You know how Nelkir said his mother is different from the one his siblings have? In my mind, this was meant to imply Irileth. She seems awfully quite devoted to Balgruuf, questionably so when she is merely meant to be a housecarl. There's just an odd air about them that seems way too intimate. As soon as Nelkir admitted that he was a half-sibling to the Jarl's children, I just KNEW it had to be Irileth. I just can't shake off the feeling of her being Nelkir's mother.
From what we know of cross breeding from the book Notes on Racial Phylogeny, the child is predominantly the race of the mother. And like Nelkir's page says it could just be lies from Mephala to manipulate him.
Evanescence of the Poison Light wrote: According to the lore, if a female mer has a child with a human, the child would have significantly more mer in them than human. If a male mer has a child with a female human, we get a Breton.
The child would resemble more of the race as the mother. Karliah being an example.
No...we don't get a Breton, we'd get a human.
Bretons are the result of unholy magicks performed by either the aldmer or the altmer. Natural breeding always results in a child the race of the mother.