LOL
Mr W will find two longish objects, give one to me and then say, "En Garde!" and begin his attack. When I get him, he lets out an "Arrrrgghg" and flops on the floor. I do the same.
Its fun and it is harmless.
I can see how you can be sensitive to this given your situation.
Oh, DD doesn't just act out fight scenes. That wouldn't bother me at all. Well, actually, it would bother me, but for a totally different reason (that being that DD is only recently out of a hitting & kicking phase that I am anxious to avoid repeating). She is very sensitive to violence, and just a bit of exposure to it can trigger a lot of acting out.
What bothers me is how much (and how) she TALKS about it. A while back she told me she had a dream in which she was at the zoo with Grandma, and they saw the elephant and the giraffes, and then Grandma killed all of the animals, and then all of the people died too, and Grandma died, and DD died. Other stuff happened too, but for some reason it wasn't as memorable for me.
And it is all said in a cheerful voice with a huge smile.
Once or twice would be fine, but it seems that nearly every story she tells involves at least one senseless death.
And then, of course, there is the deep philosophical discussion. Asking whether various relatives are still alive. Et cetera, et cetera.