Research has demonstrated that children are sexual beings and that most children engage in sexual behaviors at some point during childhood. Most of these behaviors are healthy and appropriate; however, there are some behaviors that are considered problematic behaviors (sexual behavior problems/SBPs). Given the potential for pediatricians and clinical psychologists to be initial identifiers of SBPs, these professionals need to have the knowledge and confidence to correctly identify SBPs in children. The present study was designed to shed light on similarities and differences between pediatricians and psychologists with regards to their ratings of sexual behaviors that may vary with respect to the children's gender and relationship to one another. It was hypothesized that psychologists would rate the sexual behaviors in the vignettes as more appropriate than pediatricians would. One hundred and twenty-five pediatricians and clinical psychologists in the state of Connecticut participated in this study. Participants were asked to read one of four randomly assigned vignettes depicting developmentally appropriate sexual behaviors between children that differed based on the gender of the children (same or opposite) and the relationship of the children (peers or siblings). The professionals rated the behaviors of the children in the vignettes, as well as how likely they would be to consult with a colleague about the case and how likely they would be to notify Child Protective Services of these behaviors. Results demonstrated that the relationship of the children impacted the participants' ratings of the behaviors in the vignette; professionals rated the behaviors in the vignettes as significantly more developmentally appropriate for peers than for siblings. No effects were found for the gender of the children or the relationship of the children on consulting with colleagues or notifying CPS. The results of this study are further discussed along with implications and directions for future research.