Dr. Harrop and a team of co-authors recently published an article in the American Journal of Intellectual and Developmental Disabilities extending the Behavioral Inflexibility Scales (Boyd, Bodfish, Lecavalier, and Harrop, 2018) to a sample of children with Down syndrome and Fragile X Syndrome. The findings suggest that while inflexibility is common in these conditions, it is not as common and/or interfering as our prior studies with autistic children and adolescents.