The child's mother is considered to be the woman who gave birth to him.
If a child is born within a marriage, the mother’s husband is presumed to be the child’s father. This is called the presumption of paternity. If there is doubt that the husband is really the child’s biological father, this presumption of paternity may be challenged in court.
example If a married woman is in a relationship with another man and has given birth to his child, her husband can challenge the presumption of his paternity in court.
The father of a child who is not born in wedlock is a man who acknowledges paternity or whose paternity is established by a court decision.