Merrill's backstory?

We all know that Essie was a Russian countess from the time of the Russian Revolution, Karl's a newbie, and Drew was a painter (from the 1800s?). I think Marty was a greaser from the 1950s. However, I have know idea what Merrill was before she was a vampire. Were we ever told who she originally was and if so, what episode was that in?

"I wanna, I gotta be adored."