The woman who is believed the oldest person who ever lived may have padded her real age by 23 years.
However, Russian researchers now say that the woman claiming to be Calment was actually her 99-year-old daughter, Yvonne Calment.
A new paper published by ResearchGate suggests that Jeanne Calment died in 1934 and Yvonne Calment assumed her identity so the family would not have to pay inheritance taxes, according to Inside Edition.
Some of the evidence collected by mathematician Nicolai Zak and gerontologist Valeri Novoselov include an identity card issued to Jeanne Calment in the 1930s that does not list the same hair color or height that she had later in life, according to the San Jose Mercury News.
In an interview with LeafScience.org, Novoselov said Yvonne Calment’s husband, Joseph Charles Frédéric Billot, never remarried, despite the fact that he was only 42 at the moment of her supposed death.
“There were many mentions that he was getting along very well with Jeanne and they were raising Yvonne’s son Frédéric Jean Paul together,” Novoselov said.
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He added that he checked out a birth certificate of a maid that Jeanne Calment said took her to school as a child.
“It turns out that she was 10 years younger than Jeanne, which means that she could only be taking her daughter Yvonne to school,” he said.
The researchers noted that Jeanne Calment had most of her personal papers destroyed rather than turn them over to the local archive in Arles, suggesting the family may have something to hide.
Meanwhile, Jean-Marie Robine, the French gerontologist who helped validate Jeanne Calment’s extreme age in the 1990s, is dismissing the age-faking theory as nonsense.
“All of this is incredibly shaky and rests on nothing,” he said, according to the National Post.
While researching Jeanne Calment’s claim she was born in 1875, Robine said, he and a colleague made sure to ask her questions that only she would know the answer to, such as the name of her mathematics teacher.
“Her daughter couldn’t have known that,” he said.
Robine is also skeptical that a lie of that magnitude could be kept secret for more than 80 years.
“Do you have any idea how many people would have needed to lie?” Robine said. “One day Fernand Calment starts passing off his daughter as his wife and everyone keeps quiet about it? It’s preposterous.”
The only way to determine the truth is to exhume both bodies for testing.
Should the researchers’ theory be proved correct, the new record for the world’s oldest person ever would go to Sarah Knauss, an American who died in 1999 at the age of 119, according to Inside Edition.
This article originally appeared on HuffPost.