[Bizzymammabee]

Sounds to me like she is just playing. I think if she were really being mean and aggressive she would be trying to draw blood and bear her teeth. She probably learned to play that hard and rough playing with the other three dogs as there were three of them and one of her. Just watch her and see how she progresses. Lex plays the same way with my cat April and she plays just as hard in return. When she finds him getting too rough (they don't call them terriers for nothing) she will bite him a bit harder...enough to elicite a yelp from him and he will ease up.

Good luck. Just watch her. Does she show any aggression towards your kids or yourself?