People with sickle cell disease often experience sudden episodes of severe pain, known as "pain crises." These happen when sickle-shaped red blood cells block blood flow through tiny blood vessels.

The pain can occur anywhere in the body, but it's most common in the chest, arms, legs, and back. Pain can last for a few hours to several days and sometimes requires hospital treatment.

Fatigue, or feeling extremely tired, is very common because sickled cells don't live as long as normal red blood cells.

This leads to anemia — a condition where the body doesn't have enough healthy red blood cells to carry oxygen. Without enough oxygen, the body feels weak, tired, and short of breath.

Sickle cells can block blood flow in the small blood vessels of the hands and feet, causing swelling and tenderness.

This is often one of the first signs of sickle cell disease in babies and young children. It can be painful but is usually manageable with fluids and pain relievers.

The spleen — an organ that helps fight infections — can become damaged early in people with sickle cell disease.

As a result, they are more vulnerable to infections like pneumonia, meningitis, and the flu. Preventive measures, like vaccines and sometimes daily antibiotics, are very important.

Children with sickle cell disease may grow more slowly and reach puberty later than their peers.

This happens because the body is working hard to produce red blood cells to replace the ones that die early, leaving less energy and nutrients available for growth and development.