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A teenager is fighting a devastating and rare disease that is slowly turning her into a "human statue."

Seanie Nammock, 13, suffers from fibrodysplasia ossificans progressiva, which affects only 600 people in the world, according to the International Fibrodysplasia Ossificans Progressiva Association.

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N.Y. Boy Growing Second Skeleton

The painful condition causes bone to form in muscles, tendons, ligaments and other connective tissue. Getting bumped or knocked into exacerbates the condition.

In time, bridges of extra bone develop across the joints, eventually restricting movement and forming a second skeleton that causes the body to become immobile.

Nammock's arms have frozen in a bent position while her back and neck have already started turning to “stone.” Her other body parts will gradually freeze.

The condition prevents here from washing her hair or reaching for things in her home in Ladbroke Grove, West London. She relies on friends for help.

“Not everyone knows that I shouldn’t get bumped so my friends help shield me in crowds," she said. “I leave school classes five minutes early to avoid the rush, and then me and my mates usually go and sit somewhere out of the way. I just try and do what I did before.”

There is no cure for the disease and average life expectancy for someone with FOP is 41.

Click here to read more on this story from The Sun.