But once the two girls were gone, relatives said, Ms. Trenka’s birth mother became so distraught, she began carrying a dog the same way Koreans carry children, by securing it to her back with a blanket. She was so bereft, she managed to get the adoption agency to give her the name and address of the family that had adopted the girls.

Less than three months later, she scraped together what little money she had to send traditional dresses, or hanbok, for the girls and their adoptive mother. She later sent at least two letters, which Ms. Trenka believes did not reveal the real reason for the adoption but asked about the girls’ well-being.

Although she says her adoptive parents were also victims of the Korean agency’s deception, she believes the letters should have prompted them to question the claims of abandonment. Instead, she said, they answered her early questions about her birth mother by saying that they did not know why she had been unable to care for her girls, but that they would see her in heaven. Even when she found the letters, she said, her adoptive parents did little to help her connect with her birth family, leading to an estrangement that lasted for years.

Her adoptive mother, reached by phone this week, declined to comment. Her sister, Ms. Trenka says, regards their adoption differently and stays in touch with their parents.

For Ms. Trenka, the much-longed-for meeting with her birth mother did not happen until she was 23 and had qualified for a credit card that allowed her to charge her trip. Separated by language, mother and daughter communicated through a translator. Her Korean mother, then 62, asked for her daughter’s forgiveness and bared her breasts to prove that she had breast-fed the two girls before they were separated.

Over the next five years, Ms. Trenka returned several times, before her birth mother died of cancer in 2000. They did not speak each other’s language, but Ms. Trenka said it was enough just to be with her. She slowly began to drift from the life she knew in Minnesota, eventually divorcing her American husband and writing two memoirs that connected her with other adoptees who shared her conviction that they had deserved better from their birth country.

Five years after her birth mother’s death, she left her job as a piano teacher and the sister she loves and moved to Korea.