Fantasy Mavens: What is a good title for parents in a fantasy book that takes place in another world?

Often, in fantasy books, the characters call their parents “mother” and “father.” I’ve always thought these were too stiffly formal if the parents and children had good relationships. However, “mom” and “dad” just seem too odd for a fantasy world. I have similar issues with “mama” and “papa.” I think these sound a bit too childish for an adult to call his/her parents.

So, fluther fantasy readers and writers, what would you suggest as good parental titles?