This study investigated links between interparental conflict appraisals (specifically threat and self-blame), sibling relationship quality (positive and negative dimensions), and anxiety in sibling pairs comprised of an adolescent and a younger sibling close in age. Sibling relationship quality was measured through behavioral observation. Links between self-blame and anxiety were moderated by sibling relationship quality. In older siblings, positive behavior with a sibling was associated with an attenuated relation between self-blame and anxiety. A paradoxical moderating effect was found for negative interactions; for both younger and older siblings, a relation between self-blame and anxiety was weakened in the presence of sibling negativity. Results offered support for theorized benefits of sibling relationship quality in helping early adolescents adjust to conflict between parents.