I’ve seen a few sources saying she’s been dealing with lung cancer the last few years and that’s she died of complications from that, but I’ve never heard of any of the sites before, so I won’t vouch for how reliable that info is, but that’s all I can turn up.
Dang, with her and Bob Barker, my inner child is taking a beating this week. The premiere of The Animated Series is one of my clearest childhood memories, waiting for it to start and that theme kicks in. It always amazes me she was meant to be a that character and now she’s such a big part of DC.