Anorexia nervosa (AN) is associated with clinical characteristics including eating disorder symptomatology, negative mood states, perfectionism and cognitive inflexibility. Whether these characteristics differ across illness stages, and are also present in first-degree relatives, demonstrating heritability, is unclear. The aim of this research was to compare current AN (c-AN), weight-restored AN (wr-AN), sisters of individuals with AN (AN-sis) and healthy controls (HC) on these measures.