現代人的家庭結構改獎，有許多人願意同居，但是卻不願意辦理結婚登記。在此情況下若懷孕生子，父母雙方與孩承闖的親子關係是否曾因未辦結婚登記而有不同，民眾就此多所關注。
實則，法律上之「親子關係」原則上係指父母與「婚生子女」間之關係；至於「非婚生子女」，民法第1065條第2項規定：「非婚生子女與『生母」之關係視為婚生子女。」因此，生母對於非婚生子女不需辦理認領手續；但「生父」與非婚生子女之親子關係，依民法第1065條第1項之規定（即：「非婚生子女經生父認領者，視為婚生子女。」），須辦理「認領」-生父如未「認領」該名非婚生子女，則其與非生承女閒無親子關係。
又，民法第1065條第1項規定：「（非婚生子女）經生父撫育者，視為『認領」」因此，生父若曾撫育該子女，則無須另行辦理認領手續。簡言之，如果生父不曾撫育「非婚生子女」，仍有待完成認領手續。
With changes in modern family structures, many people are willing to live together but are unwilling to register for marriage. In such cases, if a child is conceived and born, the public is highly concerned about whether the parent-child relationship between the parents and the child will be affected due to the lack of marriage registration.
In principle, the legal term "parent- child relationship" refers to the relationship between parents and their legitimate children. As for children born out of wedlock, Article 1065, Paragraph 2 of the Civil Code states: "In the relation to his mother, a child born out of wedlock is deemed to be legitimate." Therefore, the birth mother does not need to go through an acknowledgement procedure for a child born out of wedlock. However the biolosical father must ao through an acknowledgement. procedure according to Article 1065, Paragraph 1 of the Civil Code, which states: "An child born out of wedlock who has been acknowledged bx the natural father isn deemed ta be lesitimate" If the biological father does not acknowledge the childn then there is na legal parent-child relationshie between him and the child."
Furthermore, Article 1065, Paragraph 1 of the Civil Code provides: "If a child born out of wedlock is raised by the biological father, it shall be deemed as an acknowledgement." Therefore, if the biological father has raised the child, there is no need to go through a separate acknowledgement procedure. In short, if the biological father has not raised the child born out of wedlock, then a formal acknowledgement is still required.