A broad range of sexual behaviours exhibited by children is common in the normal course of human sexual development. However, these behaviours may be problematic when they become developmentally inappropriate or potentially harmful to them or others. The authors hypothesized that sexual abuse and family sexuality are better predictors of problematic sexual behaviour (PSB), whereas other forms of maltreatment (e.g., physical abuse) are more strongly associated with externalizing problems (EP). Secondary data from a study initially undertaken in 2004 was utilized. A total of 756 families who were referred to a child welfare agency in Quebec participated in the original research. This current study focuses on children between six to 11 years and their families (n=188). The study measures child internalizing and externalizing behaviour, child sexual behaviours, family sexuality, neglect, child sexual abuse, and child experiences of verbal and physical maltreatment. Findings suggest PSB is more strongly associated with family sexuality (e.g., cosleeping, cobathing, witnessing intercourse), whereas EP is more strongly associated with neglect (e.g., lack of parental supervision). The presence of verbal abuse is the only significant predictor common to PSB and EP. Surprisingly, physical abuse did not surface as a significant predictor of EP.