What is the "Death Rattle"?

”...a rattling or gurgling sound produced by air passing through mucus in the lungs and air passages of a dying person…”
-from Merriam-Webster’s New Collegiate Dictionary, 11th ed.

It is terrifying. My Mom described hearing her grandmother do it.

Thankfully when my mom was dying this didn’t happen. I’m not sure what all they did, but I would not have been able to stand that.

I guess ny FIL made that sound the day before he died. I guess the body just stops moving anything along. ;(
I saw video he asked folks to take. In it he said “So long boys! I’ll see you at the Pearly Gates.” And he had that choking breathing.