I'm going through this now and trying to find a solution. My case started out much like yours but it has now progressed to where Maggie is attacking Buster. When I give them treats, Maggie will come running over and literally push Buster out of the way with her butt. I really had to watch her when he had his knee surgeries last year, she would run at him and try to knock him down, almost like they do in the hockey games. She will still do that. She will sit on the landing of the stairs and not let him pass. She has to be the first one down and the first one up. My advice is to try to nip in the bud now. I hope I find a solution soon! I've been given lots of advice and I will be trying everything I've been given to try to have peace (at least where Maggie isn't attacking Buster) between the two. I hope your situation doesn't progress to where I'm at now.
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