Who is the US Doctor who specialize in treating intellectually disabled children?

In the U.S., many doctors specialize in treating intellectually disabled children, often pediatricians with expertise in developmental and behavioral pediatrics. One notable figure is Dr. William Gardner, known for his work in pediatric neurodevelopmental disabilities. Additionally, many children's hospitals have specialized programs and teams of professionals, including pediatricians, psychologists, and speech therapists, dedicated to supporting children with intellectual disabilities.