Mary Ellen and her son Joseph recently filed the lawsuit in Milwaukee County Court, Wisconsin.

According to the complaint, in 1980, Mary, then 25, and her husband Thomas were trying to have another child but faced difficulties conceiving.

She eventually agreed with doctor Frederick Dettmann, a long-time fertility specialist, to undergo artificial insemination using sperm from an anonymous donor, believed to be a medical student.

Mary became pregnant in 1982 and gave birth to her son Joseph the following year.

Decades later, in 2024, events took an unexpected turn when Joseph discovered through a DNA test on "Ancestry.com" that doctor Dettmann was his biological father, according to the lawsuit.

"Ancestry.com" is the world's largest website for genealogical research and family history, helping users find ancestral information and discover genetic relationships.

Results from the website also revealed numerous half-siblings and other family members Joseph had never known.

According to the allegations, doctor Dettmann never informed Mary that he was using his own sperm for her insemination, and he did so without her consent.

The mother and son are now seeking unspecified damages, to be determined at trial.

The plaintiffs, mother and son. Photo: People

Joseph stated that he and his mother decided to speak out after realizing the doctor might have done the same to many others.

Through the media, he urged former patients of doctor Frederick Dettmann, drawing from his mother's case, to check their records to ensure their rights.

Doctor Dettmann, now 91 and retired in Arizona, has denied these allegations.

"The events in question occurred nearly 50 years ago. Doctor Dettmann has no recollection of the individuals making these allegations and sees no evidence supporting the plaintiffs' claims", the defendant responded through his lawyer.

Hai Thu (According to People)