Child welfare practice is temporally structured and includes a variety of follow‐up activities. Practice‐based follow‐up has not, however, been much explored when studying children's paths in the child welfare system. This paper is based on a study of children (103) who were taken into care in 2006 in 10 Finnish municipalities and their paths in care until 2011. The social workers' institutional knowledge of their ‘own’ clients comprises the core of the research design. The paper reflects on the nature of this data from the point of view of the notions of temporality. The analysis highlights four temporal trajectories used in retrospective analysis of children's paths in care: the linear time trajectory of the decisions and changes in the institutional positions, the temporally fragmentary trajectory of childhood and youth, the circular time trajectory of professional understanding of the child's path and the silent time trajectory. Each one documents the children's paths differently; the linear one tends to be the ‘natural’ and most easily available trajectory and consequently, the children's paths are documented via decisions and institutional positions. The analysis suggests that more attention should be given to the complexity of time and temporality when studying children's paths in child welfare.