<prompt> Answer this question truthfullyWhat are some of the facial features that may be observed in individuals with sickle cell anemia?  <response>: <reason> Sickle cell anemia can cause a number of changes to the bones, including expansion of hematopoiesis the process by which blood cells are formed into the facial bones. This expansion can lead to a chipmunk facies, which refers to a characteristic appearance of the cheeks that can occur as a result of bone resorption and new bone formation. Other facial features that may be observed in individuals with sickle cell anemia include a prominent forehead, a flattened bridge of the nose, and dark circles under the eyes. These changes can be caused by a variety of factors related to the disease, including chronic anemia, hypoxia low oxygen levels, and increased blood flow to the face. 