Young children who experience abuse, neglect, domestic violence, and other interpersonal forms of trauma are at risk for developing complex psychological trauma. Timely referrals by child welfare services for trauma evaluation and intervention is critical, particularly during the developmentally-sensitive period of birth to three. However, few screening instruments exist that are feasible for implementation in child welfare services and none have reported psychometric data for children under three. The aim of this exploratory, retrospective study was to examine developmental differences in detection rates of two brief trauma screening scales, comparing outcomes for toddlers (age 1 and 2 years) and preschoolers (age 3 to 6 years), using the evaluation data from a statewide child welfare demonstration project. The sample included 151 children ages 1 to 6 participating in evidence-based trauma treatment with their caregivers. More than 80% of children, regardless of age group, met the cut-off on one of the screeners; children who met the cut-off on either screener were significantly more likely to have experienced domestic violence, physical abuse or poly-victimization. Implications for future research are discussed.