Well, it finally happened...the other day, Charlie was doing his in between the shower curtain and the liner thing while I showered, and he slipped and fell right into the tub! He scrambled out really quickly, though, and he only got a little wet.
Ever since that incident, he hasn't hung out there while I shower anymore. He'll do it when the shower is not running, but as soon as the shower goes on, he's outta there!!