Like many 3-year-olds, Ava Davis is a little shy. Her mom, Roxanne Davis, said Ava is never sure what a stranger wants from her because for most of her life she has been in and out of so many doctor's offices.

After a wellness check when she was 5 months old, Ava was diagnosed with restrictive cardiomyopathy, which refers to a group of disorders in which the heart chambers are unable to fill with blood properly because of stiffness of the heart. In restrictive cardiomyopathy, the heart is normal in size or only slightly enlarged, but it cannot relax normally during the time between heartbeats in which the blood returns from the body to the heart. Later in the disease, the heart may not pump blood efficiently. The abnormal heart function can affect the lungs, liver and other body systems.