An otherwise healthy 7-month-old infant boy presented for evaluation of a rash in a discrete area of skin on his right arm. His parents had noted a brown plaque at the site of the rash since birth. The plaque had grown in proportion to the patient's overall growth. The associated rash developed at approximately 4 months of age and was not apparently bothersome to the patient. On examination, there was a discrete 2.0 × 1.3–cm, oval, monotonous brown plaque on his right elbow with overlying scale crust and a surrounding rim of scale crust and subtle erythema (Figure 1). The remainder of the examination results were unremarkable.