This should only be used if the child has the physiological inability to move. Otherwise, tough love is needed to encourage the child to develop the skills needed to be mobile. I have a infant son with Down's, I noticed one of their children in the program also has Down's, a vast majority of children with that syndrome can and should be encouraged to walk. Walking and reciprocal motion are not just physical, there have been many links that find that babies that skip a crawling stage (i.e. go straight to walking) suffer with other academic and social skills later. There's some sort of causal link between learning to locomote on your own and higher brain function. Putting a child, like a down's child, in that machine takes away his incentive to learn this skill and will affect him adversely.