Fibula.

The doctors took a fibula bone from my leg and some tissue from my shoulder to fashion into a new jaw.

Then he took my fibula from my calf, cut it out and then relocated it to my thigh, where it now lives.

And, because I was born without the fibula bones, and had feet turned in, and a few toes in this foot and a few toes in that, he had to be the bearer this stranger had to be the bearer of bad news.