GRASSE, France » When Sophie Serrano finally held her daughter, Manon, in her arms after the newborn, suffering from jaundice, had been placed under artificial light, she was taken aback by the baby’s thick tufts of hair.

"I hadn’t noticed it before and it surprised me," Serrano said in an interview at her home here in southern France, not far from the Cote d’Azur.

Serrano, now 39, was baffled again a year later, when she noticed that her baby’s hair had grown frizzy and that her skin color was darker than hers or her partner’s.

But her love for the child trumped any doubts. Even as her relationship unraveled, in part, she said, over her partner’s suspicions, she painstakingly looked after the baby until a paternity test more than 10 years later showed that neither she nor her partner were Manon’s biological parents. Serrano later found out that a nurse had accidentally switched babies and given them to the wrong mothers.

The story made headlines in France for the first time this month, when a southern court ordered the clinic in Cannes where the babies were switched, as well as their insurer, to pay a total of 1.88 million euros ($2.13 million) to the families. The money, Serrano said, would repair "an invaluable damage" and put an end to a 12-year ordeal.

Tales of swapped newborns tend to crop up in popular culture, most recently in the ABC Family television series "Switched at Birth," in which two teenage girls learn that they were mistakenly swapped in a hospital and their families try to live together for the girls’ well-being.

But the story of Manon and her accidental mother takes turns more complicated than most fiction could anticipate, challenging cherished assumptions about maternal attachment.

Serrano’s love for Manon, she said, grew stronger after she learned that the girl was not her biological daughter. She also said that, after meeting the girl she had given birth to, she felt no particular connection with her.

"It is not the blood that makes a family," Serrano said. "What makes a family is what we build together, what we tell each other. And I have created a wonderful bond with my nonbiological daughter."

The court decision ended Serrano’s long struggle to obtain damages for the nurse’s negligence. It also helped her, she said, silence those neighbors and others who accused her of lacking maternal instinct and criticized her inability to identify with her own child.

"After four days, how can you not recognize your baby?" Sophie Chas, the lawyer for the clinic, told the newspaper Le Figaro. "We can believe in it when it’s a second, a day, two days. But 10 years? The mothers may have been involved in creating the damage."

Serrano answers such disbelief by pointing out that she was 18 at the time and that Manon, now 20, was her first child. "I could never have imagined such a scenario," she said.

When Serrano gave birth, the baby developed neonatal jaundice and was almost immediately placed in an incubator. Because of a shortage of cradles, a nurse put the naked baby in the same cradle as another naked baby.

Daniel Verstraete, the lawyer for the other family, which refused to speak publicly about the case, said that only one of the two babies was wearing an identification tag, which "may have fallen off."

When Manon was handed over to Serrano after the treatment, mother and child had spent very little time together. Serrano noticed that the baby’s hair was thicker, but she said she was persuaded to put it out of her mind.

"The nurse said that the lights from the phototherapy treatment made the baby’s hair grow," Serrano said. "I trusted medical people. I was young, I wouldn’t question their competence."

The other mother, also 18 at the time, asked another nurse why her baby lacked hair. She was told that phototherapy could also shorten hair.

"My client didn’t ask herself questions," Verstraete said. "A baby swap was unthinkable. She didn’t react because medical authority told her that she shouldn’t worry."

Serrano, who lived with her partner in a tiny village near Grasse, raised her child while facing growing suspicion from neighbors that Manon, so physically dissimilar to her parents, might have been the "postman’s daughter."

The relationship eventually collapsed, in part, Serrano said, because her partner was also suspicious and refused to care for Manon. When they separated, her partner demanded a paternity test, saying he did not want to pay child support for a girl he did not consider his own.

"I believed that a paternity test would be a relief for both of us," Serrano said.

On the contrary, the test revealed that Manon, 10 at the time, was not his child, but that she was not Serrano’s either.

"It had the effect of a tsunami," Serrano said. "I felt tremendous anxiety, the worst anxiety that one can ever feel."

"All of a sudden," she added, "you learn that you don’t know where the child you have brought into the world is. I wondered how I could find my child. And I suddenly recalled the baby hair episode."

In order to find to whom her biological daughter had been given, Serrano filed a civil complaint against the clinic in 2010. Police investigators discovered that Manon’s biological parents were a Creole couple from the island of La Réunion, a French territory in the Indian Ocean, who, as it turned out, now lived just a few miles away.

"When I first met them, I noticed how much I looked like them," said Manon, a wide-eyed young woman who studies management at a nearby technical school. "But I was sitting in front of complete strangers, and I didn’t know how to position myself."

Her biological parents are modest workers who raised their own daughter — Serrano’s birth child — "rather strictly," said Verstraete, their lawyer.

"The mother would wake up every morning thinking that she had never been able to recognize her daughter," he added. "It is not a physical wound. It is a moral suffering that will never go out."

The families saw each other several times, during which Manon explored her Creole origins. But the parents and daughters had trouble building any rapport, and they eventually stopped seeing each other. In the end, after some discussion, both families preferred to keep the child they had raised, rather than taking their biological one.

"I realized that we were very different, and we didn’t approach life in the same way," Serrano said. "My biological daughter looked like me, but I suddenly realized that I had given birth to a person I didn’t know, and I was no longer the mother of that child."

On a recent day, Serrano and Manon sat at the dining table of their modern apartment in Grasse for a lunch break.

Serrano said she was recovering from years of depression. She is unemployed and has two other children from another relationship since her separation. Her frail physique and reserved manners contrasted with Manon’s outspokenness and athletic build.

Neither of the two women said how they would spend the money from the trial, but Manon said she dreamed of settling in Britain and pursuing a career in management.

"The story of my birth has made me stronger," Manon said as she ate French fries out of an orange fast food container. She found balance, she said, through therapy, her mother’s love and her own "deeply ingrained" pragmatism.

"I tend to never leave anything to chance," she said with a smile. "Now I even try to anticipate the unthinkable."

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