Barbara was blocking the door, but she wheeled back a bit to let Charlie out, even though Charlie was probably just as apt to bounce past. (It seemed like silent approaches were simply inherent to all members of the Bat-family, whether or not they used their feet.) Her expression was layered, concern and sorrow, but she gave Charlie a small smile for what she knew without checking any records (as she tried not to) must have been an unsuccessful attempt at comforting Cass.