Damon Muller was diagnosed with rare autoimmune disease in only five months . The 11-year-old ca n't go out in the sun or be active due to muscle swelling . He was rushed to a Brisbane hospital because his throat closed over and there 's a chance his heart could be affected too . Juvenile Dermatomyositis effects muscles including thighs , hips and chest .
Damon Muller was diagnosed with rare autoimmune disease in November . The 11-year-old ca n't go out in the sun or be active due to muscle swelling . He was rushed to a Brisbane hospital because his throat closed over and there 's a chance his heart could be affected too . Juvenile Dermatomyositis effects muscles including thighs , hips and chest .