Raised a son for 10 years, but his blood type suggests he may be someone else’s child? ... “A college senior is his biological father—am I going to lose my son?” [The Law]
- Input
- 2026-10-28 13:44:14
- Updated
- 2026-10-28 13:44:14

[Financial News] A man who learned that the son he had raised for 10 years might be the child of his wife’s ex-boyfriend sought legal advice.
College senior who learned belatedly that he was the biological father: “I want to find my son”
On the 28th, YTN Radio’s “Attorney Jo In-seop’s Counseling Center” featured the story of A, who had been married for 10 years.
A began by saying, “My wife and I were college classmates. When we were in college, my wife was so beautiful that everyone acknowledged it.”
At the time, his wife had a boyfriend who was one year ahead of her in college, and A says he suffered in silence, keeping his feelings to himself.
A said, “One day, I heard that the two of them had broken up. I comforted my wife, and we gradually grew closer. We happened to spend a night together, and shortly afterward I learned she was pregnant, so we immediately registered our marriage and held a wedding.”
He confided, “The 10 years since my son was born have been like a dream. But a few months ago, while my son was in the hospital, I found out that my wife and I are both type A, while my son is type B.”
He continued, “I thought something was strange and asked my wife. She suddenly burst into tears and told me something hard to believe: our son might not be my biological son. She said that the college senior she had dated before marrying me was probably the child’s biological father.”
Shaken, A met with a close college classmate and confided in them. Later, the senior, who was the child’s biological father, appeared. He reportedly said he wanted to find his biological son and demanded that he establish a legal parent-child relationship with the boy and be allowed to meet A’s wife separately.
A sought advice, saying, “In all the years I’ve raised my son, I’ve never once thought I wasn’t his father. If that senior really is my son’s biological father, will I lose my legal status as his father? In that case, whom does the law recognize as the child’s father?”
Lawyer: “Blood ties alone do not determine legal parentage”
Attorney Park I-chan explained, “Even if it is revealed that a child born during a marriage is not biologically related to the husband, that fact alone does not immediately end the legal parent-child relationship. Even if a DNA test can establish that someone is the biological father, he must follow the procedures prescribed by law to become the legal father.”
Attorney Park said, “If the person who shared this story wants to end the legal father-son relationship because he is not biologically related to his son, he cannot do so simply by expressing an intention to sever family ties. If the presumption of paternity applies, he must, in principle, contest the parent-child relationship through an action to deny paternity, as provided for in the Civil Act.”
He added, “Because there is a fixed time limit for filing an action to deny paternity, it is important to establish when the person learned there was a problem with the parent-child relationship and to clarify the specific family relationships involved. Ultimately, resolving a legal parent-child relationship requires following the procedures and requirements set out by law, not simply making an emotional declaration,” he advised.
They say knowledge of the law is power. [The Law] features lawyers’ advice on a range of legal disputes. Subscribe to the series to receive it conveniently.
[email protected] Kim Su-yeon Reporter