I hate to say it but you have a serious dilemma on your hands here with a baby on the way even if you calm the situation now - after what you described happened on the basketball court the aussie X could flare at any time do you really want this with a young baby around!!!! I think it is a case of sadly rehoming the aussie x to be able to live in harmony with the other two it is going to be hard enough to get them to live along together without the addition of a new baby on the scene as some dogs do find this hard to cope with anyway.

Please think seriously about what you are about to take on board and the main priority will be the new baby, it will not be an easy decision but one that would be easier to make sooner rather than later.

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