Historically, immigration referred to these children as illegitimate if their parents were not married at the time of the children’s birth. Congress amended the definition of Child by replacing the words illegitimate child with child born out of wedlock and legitimate child with child born in wedlock.If a child’s parents are not married at the time of birth, he or she is considered a child born out of wedlock. Such a child can immigrate through his or her mother without any problems. But if the child tries to immigrate through the father, they must prove that the father has a bona fide parental relationship with the child before the child reaches the age of 21. Meaning the father must have shown an actual concern for the child’s support, instruction and general welfare.  The family also must prove that the father is the natural father.