@simrin-- Those kinds of bone dysplasia are often lethal aren't they? I read that about five percent of dysplasia cases in fetuses end with death during birth. It's because the bone growth is too small to allow lungs to fully develop and the infant dies immediately after birth.
I think your friend's daughter must not have had a really bad case of dysplasia. Otherwise, it would have been hard for her to get through infancy.
I agree with you about early diagnosis. The other thing is that diagnosis during the fetal stage is always incomplete because you will not know exactly which type of dysplasia you're dealing with until the child is born and older.
There are hundreds of different types. Genetic testing can help with that but I don't think doctors take amniotic fluid for genetic testing very often. Because that can put the life of the child at risk too.