Background/ObjectiveBereaved family surrogates from intensive care units (ICU) are at risk of comorbid anxiety, depression, and post-traumatic stress disorder (PTSD), but the temporal reciprocal relationships among them have only been examined once among veterans. This study aimed to longitudinally investigate these never-before-examined temporal reciprocal relationships for ICU family members over their first two bereavement years.MethodsIn this prospective, longitudinal, observational study, symptoms of anxiety, depression, and PTSD were assessed among 321 family surrogates of ICU decedents from 2 academically affiliated hospitals in Taiwan by the anxiety and depression subscales of the Hospital Anxiety and Depression Scale, and the Impact of Event Scale-Revised, respectively at 1, 3, 6, 13, 18, and 24 months postloss. Cross-lagged panel modeling was conducted to longitudinally examine the temporal reciprocal relationships among anxiety, depression, and PTSD.ResultsExamined psychological-distress levels were markedly stable over the first 2 bereavement years: autoregressive coefficients for symptoms of anxiety, depression, and PTSD were 0.585–0.770, 0.546–0.780, and 0.440–0.780, respectively. Cross-lag coefficients showed depressive symptoms predicted PTSD symptoms in the first bereavement year, whereas PTSD symptoms predicted depressive symptoms in the second bereavement year. Anxiety symptoms predicted symptoms of depression and PTSD at 13 and 24 months postloss, whereas depressive symptoms predicted anxiety symptoms at 3 and 6 months postloss while PTSD symptoms predicted anxiety symptoms during the second bereavement year.ConclusionsDifferent patterns of temporal relationships among symptoms of anxiety, depression, and PTSD over the first 2 bereavement years present important opportunities to target symptoms of specific psychological distress at different points during bereavement to prevent the onset, exacerbation, or maintenance of subsequent psychological distress.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12888-023-04916-4.