Abstract Background Fragile X syndrome (FXS) is a genetic disorder that is highly comorbid with anxiety and autism spectrum disorder (ASD). Elevated negative affect in young children has been associated with increased risk for both anxiety and ASD; however. these relations remain poorly understood in FXS. Methods The present prospective longitudinal study examined the trajectory of ne... https://bellfordtoysandhobbiers.shop/product-category/hobby-paint/