I remember when I first heard this news, it hit me like a freight train. For some reason I would have thought we had many more years left with Yvonne, but I guess it wasn’t meant to be...
"Batman told him a super funny joke. When the creature didn't laugh, that was proof!"
The news really hit me hard, too. IIRC, at the time I recently had responded to the announcement that Adam, Burt and Julie would be voicing their respective characters in "Return of the Caped Crusaders" by expressing the hope that they would get Yvonne on board with the project as well. I was unaware of her health issues, so when the news came shortly afterward, I was devastated. RIP, Yvonne.