OBJECTIVE: Chinese shidu parents (bereaved parents who have lost the only child) may experience prolonged grief disorder, as well as posttraumatic growth (PTG). This study aimed to examine their latent classes and transition patterns of prolonged grief disorder symptoms and PTG. METHOD: Based on a longitudinal design, 265 shidu parents completed the Prolonged Grief Scale-Revised and Short Form of Posttraumatic Growth Inventory for Chinese Shidu Parents twice with an interval of about 5 months. Latent class analysis and latent transition analysis were performed to identify subgroups and their transition possibilities over time. RESULTS: Four latent classes that changed over time were identified: a "growth" class, a "combined grief and growth" class, a "low grief" class, and a "high grief" class. From Time 1 to Time 2, the proportion of the growth class and the low grief class increased. Shidu parents in the growth class or combined class had about a 36% probability of moving to low grief class. Compared with individuals in the high grief class (8.5%), members in the low grief class (20.4%) had a higher probability of moving to the growth class. Moreover, 29.0% of shidu parents suffered from persistent grief. CONCLUSIONS: Adjustment to child loss displayed substantial variations between individuals. PTG reported by shidu parents can be both stable and temporary. About 30% of shidu parents suffered from persistent and severe grief, and designing grief-focused treatment may be beneficial for them. (PsycInfo Database Record (c) 2025 APA, all rights reserved).