This article contextualizes the exploration of sibling homicide, or siblicide, a phenomenon that traditionally has received very little attention within the academic literature. Siblicide is examined in relation to other family homicides and other known homicides. Given the traditional frequency, duration, and intensity of youthful sibling relationships, juvenile homicides are disaggregated from adult homicides to reveal whether there are any differences. Although previous research has questioned the use of the Supplementary Homicide Reports for this type of analysis (Daly, Wilson, Salmon, Hiraiwa-Hasegawa, & Hasegawa 2001), the utility of the data set is demonstrated. The results of this exploration suggest that siblicide may be examined within the theoretical contexts of sociobiology and routine activities theory.