Was Olivia's maiden name ever revealed? And what about her parents? Weren't they ever mentioned in the series run?

I don't think we know Olivia's maiden name. I know she had brothers, and Aunt Kate, but I think that's as much of her family as we know about. Could be wrong though.

Well, it is revealed in season 1 (which I'm currently watching), than Olivia grew up on Walton's Mountain and that she knew John as a child. They started courting in high-school. I'm guessing her parents must have been deceased.

Olivia does mention in one episode that her parents "have been gone this long time" so they must have past away a long time ago.

Her maiden name is Daly..

http://waltonswebpage.proboards.com/thread/1061/olivias-background?page=1#