Ruby, absolutely fantastic poster. The little toy trucks make it so sad
I would have thought by now, somebody would know who this little guy is. I am thinking that he may not be enrolled in school. Special needs kids who are homebound recieve tutors from the district, so the kids are followed by a teacher but do not go to school regularly. He also may not yet be enrolled in school yet, especially if he is five and not six. Many of the kids I care for (all with special needs) started school a year late because they needed an extra year to mature. However, all kids with special needs that are preschool aged are eligible for free preschool programs to address their disabilities.
I think that the Shriner's Hospitals need to be contacted to see if anyone recognizes the child. Also, parent support group for children with special needs. Somebody may think this kid has moved, but in reality, he hasn't.
If more were released on his medical information, you might get a whole lot more leads. For example if you knew he had this syndrome, then you would look at these doctors, etc. Some kids require very specialized diets so the nutritional suppliers may be able to narrow kids down, or perhaps police using a list provided.
I have a student who used to be on a feeding tube. She is really tiny, but the reason they are put on a feeding tube in the first place is that they are unable to either eat regular food, process regular food, etc, so I don't think the poor child was starved like other people do.
Edited to add: I think his picture also needs to be shown to geneticists. If he has a rare genetic disorder, it would be pretty easy to pin down his identity. I've taught a lot of children with all sorts of special needs and his face type doesn't look familiar to me.