Background and Objective: Outcomes for children with special health care needs (SHCN) can vary by their patterns and persistence over time. We aimed to empirically establish typical SHCN trajectories throughout childhood and their predictive relationships with child and parent outcomes. Methods: The 2 cohorts of the nationally representative Longitudinal Study of Australian Children were recruited in 2004 at ages 0 to 1 (n = 5107, B cohort) and 4 to 5 years (n = 4983, K cohort). The parent-reported Children With SHCN Screener (Short Form) was completed at each of 4 biennial waves. Wave 4 outcomes were parent-reported behavior and health-related quality of life, teacher-reported learning, and directly assessed cognition. Both parents self-reported mental distress. We derived intracohort trajectories by using latent class analysis in Mplus. We compared mean outcome scores across trajectories by using linear regression, adjusting for socioeconomic position. Results: Four distinct SHCN trajectories were replicated in both cohorts: persistent (B 6.8%, K 8.7%), emerging (B 4.1%, K 11.5%), transient (B 7.9%, K 4.2%), and none (B 81.3%, K 75.6%). Every outcome was adversely affected except fathers’ mental health. From infancy to age 6 to 7 years, the persistent and emerging groups had similarly poor outcomes. From age 4 and 5 to 10 and 11 years, outcomes were incrementally poorer on moving from none to transient to emerging and to persistent SHCN. Effect sizes were largest for behavior, learning, and psychosocial outcomes. Conclusions: Adverse outcomes are shaped more by cumulative burden than point prevalence of SHCNs. In addition to providing care according to a child’s need at any given time, prioritizing care toward persistent SHCNs may have the biggest benefits for children and parents.