Carl Zimmer, writing for The Atlantic.
Peeper’s diagnosis meant that, over her lifetime, she would essentially develop a second skeleton. Within a few years, she would begin to grow new bones that would stretch across her body, some fusing to her original skeleton. Bone by bone, the disease would lock her into stillness. The Mayo doctors didn’t tell Peeper’s parents that. All they did say was that Peeper would not live long.
... “Your muscle isn’t turning to bone,” says Shore. “It’s being replaced by bone.”
Strange disease. Incredible story.