I had thought as much (difficult topic) because I think by the way you feel you would have talked with the kids about it. I think that you may want to talk to the eldest who knows about the argument just to reassure her...may not be necessary but then again, if 'daddy' keeps having a hissy fit everytime her aunt comes to visit, that can't be anything but confusing, and saddness inducing..particularly if the topic of argument is such a tragic one.

I go back to my end advise then and just suggest you stick to your guns if you believe you are right, and if possible either arrange for your H to be out of the way (relaxing somewhere, maybe with his friends) or possibly talk to his T regarding the situation.

In any event, this kind of stress cannot be good for you, and as you seem to be the only one on your end maintaining balance, it is essential that you take care of yourself, emotionally and physically.