Most children with Down syndrome have:

*Distinctive facial features, such as a flat face, small ears, slanting eyes, and a small mouth.
*A short neck and short arms and legs.
*Low muscle tone and loose joints. Muscle tone usually improves by late childhood.
*Below-average intelligence.
Many children with Down syndrome are also born with heart, intestine, ear, or breathing problems. These health conditions often lead to other problems, such as airway (respiratory) infections or hearing loss. But most of these problems can be treated.