This is a comment on Eragon's parentage and foreshadows the revelation, in Brisingr, that Brom is Eragon's father: Like any siblings, Murtagh and Eragon share parents (while two may share two). Their mother, Selena, was certainly the same (and one of two is certainly one). But their father may not necessarily be (One might be two). Brisingr showed that this is indeed the case - they are half-brothers: while Murtagh is the son of Morzan by his wife Selena, Eragon is not, and Brom was his true father. I didn't guess this answer. It was copy/paste from here - http://inheritance.wikia.com/wiki/Blagden
