A rare disease has left a young Australian boy at risk of being trapped in his own body, news.com.au reported. 

Jarvis, 3, suffers from fibrodysplasia ossificans progressive, which has been dubbed “human mannequin disease.” The disorder causes muscle tissue and connective tissue to gradually be replaced by bone, forming bone outside the skeleton and restricting movement.

Whenever Jarvis falls, he runs the risk of his joints seizing uncontrollably and triggering abnormal bone growth.

Jarvis is one of 13 people in Australia diagnosed with the condition. According to the National Institutes of Health (NIH), the rare disorder is believed to occur in only about one in two million people worldwide.

The boy’s mother, Lara Boniface, 40, is fighting for any answers she can get.

“We don’t know when it’s going to start, when he will have a flare up and we still want to raise a normal, strong little boy. I don’t want to put him in a bubble and turn him into someone who’s scared all the time,” she told news.com.au.

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