When BOTH parents have sickle cell trait (AS), the child may inherit:

• two normal hemoglobin genes, or
• one normal hemoglobin gene and one sickle cell gene, or
• two sickle cell genes

With EACH pregnancy there is a:

• 25% chance that the baby's red blood cells will be normal (AA).
• 50% chance that the baby will have sickle cell trait (AS).
• 25% chance that the baby will have sickle cell disease (SS).