"By the age of 40, 100 percent of all individuals with Down syndrome have the pathology of Alzheimer's in their brain," Rafii

With our advances in medical care, many down syndrome individuals can now live up to age 60, where they will have dementia.

"People With Down Syndrome Are Pioneers In Alzheimer's Research"
Source: NPR

Definite ethical dilemma for families with down syndrome family member(s).
However, it is an important note for families in what to prepare for.