Originally Posted by
bat39
Well...not too sure about that. Wasn't it one of those ambiguous things where they pretty much ignored Silver Age stuff until Morrison officially brought it back and made it relevant again?
I mean, there's that photo of the 50's Bat-family, including Kathy, in the Batcave in TKK - then again, TKJ's canonicity itself wasn't 100% assured when it first came out.
Regardless, as a character, Kathy was dead and nowhere on the radar when the '89 movie came out. And tonally she doesn't fit this world at all. Now Kate Kane's Batwoman might be a better fit for this world tonally, but she'd just be an out-of-place anachronistic element.