I don't think my comment helped. You had already made what I think is the main point, that a _common_ linguistic ancestor (rather than direct ancestry) is plaus

I don't think my comment helped. You had already made what I think is the main point, that a _common_ linguistic ancestor (rather than direct ancestry) is plausible between the Hun and the Navajo. But the parent comment author (which I am not) didn't say there was direct ancestry either, just that they were related. I mean we're all related to a greater or lesser extent anyway, so what difference does a direct or back migration make? I think to me, what would be most interesting is that the proposed linguistic connection wasn't from a back-migration, because then we'd have more of a linear narrative. Oversimplifying, it would be: Africans became central Asians, who became Eastern Asians, who became Americans. And I kind of feel that's how everybody else wants it to be too, a neat little linear story. Which is what I assumed you read into the parent comment, that the Navajo and Hun share a narratively pleasing close connection. So I just wanted to point out that the Navajo and Hun could be related from a non-linear perspective, and for the parent comment to still be relevant. But I think you were already ahead of me anyway! BTW, it does seem like the parent comment is implying that the Na-Dene migration occurred as a result of the collapse of the Xiongnu, which is obviously misleading, because the 2 events are something like 12,000 years apart.