There is a certain probability that harelip is inherited. Harelip is a relatively common congenital malformation, with one in every 1,000 newborns having a harelip. Genetic factors are the main cause of harelip in children. According to the law of heredity, a mother with a harelip has the highest chance of passing it on to her children. In case of consanguineous marriages, the chances of having a child with harelip are even higher. Because of the presence of genetic factors, members of the family with harelip should do the relevant pregnancy checkups and try to detect and treat it as early as possible to minimize the damage. Repair of the harelip after discovery through facial surgery can restore the relevant normal level, but it needs to be done under the guidance of a doctor.