The first time Tyler did this he was much younger and on a "time out punishment" for something he did. (Time out for us was to ignore the behavior, and/or the dog if necessary.)
Tired of being ignored, (and I'm sure he thought no one was watching) he stealthily climbed to the couch arm, then to the couch back, and sat directly behind my daughters head. He then proceeded to do the tap, tap, tap with the paw on the back of her head. Being young and irritable (can you say PMS??) the DD reached back and slapped his paw. Tyler pulled that paw back at the speed of light and b#tch slapped her right up side the head:eek:, sprang off the couch, and ran away. After a moment of stunned silence, we all just burst out laughing.
Now Tyler just uses his b#tch slap on his sister, Kate. When they both do it at the same time, usually standing on their hind legs, we call it a kangaroo boxing match:D .