Challenging behaviors including aggression, property destruction, stereotypy, and self injury occur at a high prevalence in individuals with Autism Spectrum Disorders (ASD). These behaviors are pervasive and chronic. Despite an increased probability and negative consequences, one area which has received little attention is the presence of challenging behaviors in infants and toddlers with ASD. We investigated if this pattern of problem behaviors can be detected in those with ASD at an early age. Six-hundred and twenty-four atypically developing toddlers classified as ASD (n0297) or non-ASD (n0327) were studied using the Baby and Infant SCreen for aUtIsm Traits-Part 3 (BISCUIT-Part 3). Participants were divided into four age groups: 12-18 months, 19-25 months, 26-32 months, and 33-39 months. A factorial MANCOVA was used to assess age and diagnostic group differences on BISCUITPart 3 domains. A general trend of severity of challenging behavior in infants and toddlers with ASD was noted to occur across age cohorts. Implications of the results and directions for future research are discussed.