like Dragon Age: The Silent Grove, Alistair does become the King in the canon lore of the books, in which he goes on to kill a Witch of the Wilds thankfully not Morrigan and even meet his father.
In Dragon Age: Origins, Alistair reveals that he believes his mother was a servant who died in childbirth. However, a spin-off book revealed that his mother was actually an elven Grey Warden mage ...