Research has shown that prolonged grief disorder (PGD) is a disorder distinct from other disorders including major depression and posttraumatic stress disorder (PTSD). This study aimed to extend this research by examining the distinctiveness of symptoms of PGD relative to symptoms of adult separation anxiety disorder, also taking into account depression. Data were available from 205 bereaved individuals who completed measures tapping these symptoms together with a complementary measure of mental and physical health. Findings showed that symptoms of PGD, depression, and adult separation anxiety disorder were better conceptualized as distinct dimensions instead of a unitary dimension of distress. Correlations between the three symptom clusters were moderate to large. Cause of loss was the single variable that was associated with all three symptom clusters with loss due to violent cause giving rise to more severe symptoms. All three symptom clusters were associated with lower concurrent mental and physical health.