Reagan has Down syndrome. We all know that by now right? ;) But what does that really mean? Technically speaking it means that she has Trisomy 21...that is three copies of her 21st chromosome. Instead of the 46 chromosomes (23 pairs) she has 47...shoulda known that a kid born to musical parents might have a triplet thrown in just to keep it interesting lol. Medically speaking that extra copy can contribute to a long list of possible side effects. Some of these Reagan has and some not. Her vision seems un-affected. Her hearing...not so good. Her thyroid is fine, but her heart was broken till her amazing surgeon fixed it.