Juvenile idiopathic inflammatory myopathies (JIIMs) are a group of diverse, systemic autoimmune diseases that manifest in childhood and are characterized by weakness and chronic inflammation of skeletal muscles. One of the relatively rare variants of JIIMs is juvenile polymyositis (JPM). JPM patients present with proximal and distal muscle weakness, gait instability with falls, muscle pain and tenderness, and high levels of creatine kinase (CK) during adolescence. There are currently few people being diagnosed with JPM, which raises the question of whether or not it is a distinct disease. We discuss the case of a 13-year-old girl who presented to the hospital with generalized body swelling and difficulty swallowing solid food. She also had drooling of saliva during the presentation and a history of difficulty climbing up and down the stairs for three months. Her extensive laboratory workup showed a positive antinuclear antibody (ANA) test and increased muscle enzyme. A muscle biopsy was ordered, and she was diagnosed with JPM. Such a unique presentation has rarely been reported in the pediatric literature. This case report outlines an unusual JPM presentation that could help clinicians identify the condition and start treatment as soon as possible to minimize complications.