They may have hearing problems and problems with the intestines, eyes, thyroid, and skeleton.
[medlineplus.gov]
This causes intestinal problems when they eat gluten, a protein in wheat. Hearing problems. Up to 75% of children with Down syndrome have problems with their hearing.
[familydoctor.org]
Individuals with Down syndrome are at an increased risk for heart, gastrointestinal, hematologic, respiratory, visual, sensory-motor, speech and language and hearing problems
[genetics.emory.edu]