Xenoglossia refers to a person's knowledge of a language they have never studied. Pretty random, right? I confess, X is a pretty difficult letter, but this does relate! (Ok, the random Xenoglossia Anime doesn't really relate, but how could I pass it up?)
In my latest MS, Daughter of the Moon, the main character discovers she can speak the language of the Underworld. This comes as quite a shock since she has never before heard the language until she fluently speaks the words herself. And when those spoken words result in magic, she can't pretend the language isn't real. There's a good explanation for all of this, but I don't want to give it away :)
Have you read any novels where a character suddenly speaks a language they have no known prior knowledge of? I'm looking for examples, but having a hard time finding any (and I don't mean speaking in tongues).