A 15-year-old girl was repeatedly raped over a period of six months by one of her relatives on the promise of marriage, police said today. The girl, belonging to a village located within the Gadwar police station limits, was repeatedly raped over a period of six months by her brother-in-law, Govinda Chauhan, on the promise of marriage, the police said. The accused, however, refused to marry the girl after she got pregnant. The matter came to light after the girl’s father lodged an FIR yesterday. The accused was arrested today and the victim sent to a hospital, the police said.