Both HIV and hepatitis C virus (HCV) can be transmitted from mother to child during pregnancy and delivery. Vertical transmission of HIV and HCV separately is most likely from HIV/HCV-coinfected mothers; however, transmission of both infections is less frequent. The effect of HCV coinfection on HIV-related disease remains unclear; whereas most studies indicate no effect, recent results suggest HCV in adults accelerates HIV progression. Little is known about how HIV coinfection affects HCV progression in children and the information available is based on small numbers of patients. Paediatric HIV treatment is extremely successful and it is vital to determine if HCV coinfection alters the effectiveness of this treatment. The hepatotoxicity of many HIV therapies and the possible negative impact of HCV on this treatment, alongside the interactions and contraindications of many HIV and HCV therapies, further limits the choice of paediatric treatments for coinfected children. Future research must therefore focus on vertically acquired HIV/HCV coinfection to inform treatment trials addressing coinfection management.