Subcutaneous panniculitis-like T cell lymphoma is a rare disease, characterized by a typical clinical presentation mimicking panniculitis, and is often associated with systemic symptoms including hemophagocytic syndrome. The pathogenesis and etiology of this disease is not fully understood. Here we report two patients coming from the same family. They lived together. The disease afflicted a boy and his elder sister at different time with an interval period of 11 years. Both of them had hemophagocytic syndrome preceding the full-blown manifestations of the lymphoma. However, severity of the disease and the response to chemotherapy is quite different between the two siblings.