Hi there, we're new here & need some help...Otis, my almost 4 month old little man, is a little terror!!!
He LOVES to play chase, and has taken to chasing my girls(ages 4 & 2) and growling and attacking their ankles. I've been acting as a body guard to my girls when we're all outside together, reprimanding him with a "No Bite!" and trying to re-direct his attention to a toy. If he is still persistent, he ends up in his corral, isolated.

It is SOOO exasperating... Also, lately if he's really riled up, he's taken to jumping around, landing in a play stance and growling/biting at ME!!! When this happens, he gets more reprimands, "No Bark!" and gets a time out gated in the laundry area.
I need advice on two things:
1- I realize that attacking the girls' ankles is COMPLETELY unacceptable, but I need some more advice on how to curb this behavior.
2- Also, in regards to the growling/barking play stance with me, I'm having a having a hard time determining how much is acceptable play, or if it's aggression.
Otis is our first small dog, we've owned a Golden Retriever and a Lab. So the training has come as bit of a challenge in comparison to our others. My husband has never been on board with getting a small dog(although he has softened up to him) So the training and care of Otis is on me. I really need to get a handle on this behavior and prevent it from escalating...
Thank you so much for any advice you can offer.
Nicole & Otis