Hey Kay,

Just wondering, Sport and Chewy are fairly close in age right? If that's the case the reason Sport might be acting so aggresively towards Chewy is that she's trying to challenge her for her place in the pack or at least establish which of them is the more dominate dog. If that's the case then the only advise i can give is let them sort it out.

If Sport starts to get after Chewy let her, Chewy will then have to defend herself instead of depending on mom to defend her which could be part of the problem. I know it sounds kind of harsh and stuff but if that's the probelm it could be the only way to help put an end to it. If things get to harsh however like blood and stuff then by all means jump in, but if otherwise just stand off to the side and let things happen.

All dogs go through this, Smudge and Winter went through it for a short period of time, all of my friends dogs go through it, my friends actually going through with it right now with her dogs.

Letting them sort through it on their own is probably the best way tough because if you keep correcting Sport when she starts after Chewy it could actually breed even more agression not only towards Chewy and other dogs.

Hope this helps
Tracy