Stiff Person Syndrome (SPS), is a very rare neuroimmunologic disorder characterized by progressive muscle pain, rigidity, stiffness, and spasms. It can be very debilitating if misdiagnosed or not recognized in time. Herein we discuss a case of a female in her 20s who presented with an unsteady gait, lower extremity weakness, persistent leg pain, and stiffness few weeks after uncomplicated childbirth. She has type 1 diabetes mellitus (DM) and was diagnosed with thyroiditis in the course of her illness. The triad of thyroiditis, DM, and stiffness with normal neuroimaging in a young female patient is an unusual occurrence.