The goal of this project was to construct a novel linked administrative dataset that includes population-level information on births, hospitalizations, deaths and child protective system (CPS) records for Washington State 2010-2021. The dataset, linked at the child-level, can be used to examine how children with concerns of child maltreatment interact between and within medical and CPS systems, including during the COVID-19 pandemic. The volume of data made common off-the-shelf approaches to data linkages infeasible.