To evaluate in the Netherlands the national outcomes in providing cause of and insights into sudden and unexplained child deaths among children via the Postmortem Evaluation of Sudden Unexplained Death in Children (PESUDY) procedure. Suddenly deceased children aged 0-18 years in the Netherlands were included in the PESUDY procedure if their death was unexplained and their parents gave consent. The PESUDY procedure consists of pediatric and forensic examination, biochemical, and microbiological tests; radiological imaging; autopsy; and multidisciplinary discussion. Data on history, modifiable factors, prior symptoms, performed diagnostics, and cause of death were collected between October 2016 and December 2021. 212 cases (median age 11 months, 56% boys, 33% comorbidity) were included. Microbiological, toxicological, and metabolic testing was performed in 93%, 34% and 32% of cases. In 95% a CT scan or MRI was done and in 62% an autopsy was performed. The cause of death was explained in 58% of cases and a plausible cause was identified in an additional 13%. Most children died from infectious diseases. Non-infectious cardiac causes were the second leading cause of death found. Modifiable factors were identified in 24% of non-SIDS/USID cases and mostly involved overlooked alarming symptoms. The PESUDY procedure is valuable and effective for determining the cause of death in children with sudden unexplained deaths and for providing answers to grieving parents and involved health care professionals.