Within the United States, close to 45 million youths between the ages of 6 and 18 participate in some form of organized sports. While recent reviews have shown the positive effects of youth sport participation on youth health, there are also several negative factors surrounding the youth sport environment. To date, a comprehensive review of the negative physical and psychological effects of organized sport on youth has not been done and little thus far has documented the effect organized sport has on other players within a family, particularly on parents and siblings. Therefore the purpose of this paper is to conduct a review of studies on the negative effects of organized sport on the youth athlete and their parents and siblings. Articles were found by searching multiple databases (Physical Education Index and Sociology, Psychology databases (Proquest), SPORTDiscus and Health, History, Management databases (EBSCOhost), Science, Social Science, Arts and Humanities on Web of Science (ISI), SCOPUS and Scirus (Elsevier). Results show the darker side of organized sport for actors within the family unit. A model is proposed to explain under which circumstances sport leads to positive versus negative outcomes, ideas for future research are drawn and recommendations are made to optimize the youth sport experience and family health.