HAHA, Tyra falls off tables/couch/bed/windowsill when she's asleep too! And the both of them have mouth movement when sleeping... kind of like chattering teeth/lip smacking. Maybe they're dreaming about fooooood... :lol:
I would also bet she is dreaming. Velvet will meow, move and make little crying noises when she dreams. It is actually pretty cute and funny. I made the mistake of reaching down and attempting to comfort her when I thought she was upset. I must have scared her. She woke up hissing, snarling, her tail was all puffed up.
Lesson learned, do not awaken a sleeping cat! :wink: