Nature's cruel and in modern society there's a shrinking place for people without advanced skills. And odds are that a child with a cognitive disability like that wouldn't be able to have advanced skills. So the child is nearly always going to be put into the "Have not" category. A human isn't a pet, and having a child who is always going to struggle to be independent isn't good for society, or anyone involved. With modern medicine we can stop alot of cruelty, like childhood illnesses and such, and we can also screen for these things. Not only this, but the resources taken could've been given to others with far more potential. You could deny child #2 from being a doctor due to the resources that must be given to child #1, and robbing one child for another isn't right, especially when it's wasted.