A 10-week-old infant girl was referred to our hospital with a rapidly growing lesion involving the right orbit. The infant was twin B of nonidentical twins and born prematurely at 29 weeks' gestation. The lesion had been present at birth as a flat purplish mark and had started to increase in size from the age of 10 days. On examination, a large, soft periocular mass was observed and had been completely occluding the right eye from the age of 5 weeks (Figure 1 and Figure 2). The baby was otherwise well. A complete blood cell count and results of coagulation tests and a basic chemistry panel were all normal. Following further diagnostic investigations and therapeutic interventions, the infant required surgical treatment at the age of 17 weeks (Figure 3 and Figure 4).