Starting in childhood, Klam had been captivated by the rags-to-riches story of four older cousins (first cousins twice removed, to be exact) collectively referred to as the Morris Sisters. Their saga brimmed with trauma, tragedy and hard-won success. Three of the four were born into poverty in rural Romania, which the family fled for America amid threats of antisemitic pogroms. Soon after the family settled in St. Louis, the girls’ mother, Clara, died giving birth to the fourth sister. Soon after that, their father, Guerson, abandoned all four girls — Selma, Malvina, Marcella and Ruth — to be brought up in an orphanage. He was never heard from again.

And yet, by virtue of their hard work and business smarts (and a rumored affair between Marcella and J.P. Morgan), the sisters made their way to New York City, where, never marrying or depending on anyone but themselves, they lived together for decades under one roof. After their deaths (the last died in 1995 at the age of 93), they left an estate worth millions.

For Klam, this was a triumphant tale of independent women who had succeeded on their own terms in a pre-Ms. Magazine age of blatant chauvinism. And it spoke to her all the more when she reached adulthood and could not help but wonder: How had these sisters forged lives of such self-sufficiency in the first decades of the 20th century, when she, on the verge of a divorce in the 21st century, was having trouble reinventing a life that was not dependent on a man? Could she discover in her DNA some of the moxie that had served them so well?

She set out to uncover as much about them as she could — and immediately hit a wall of obfuscations, embellishments and flat-out lies. That tidbit about the affair with J.P. Morgan? Impossible: He had died in Italy in 1913, when Marcella was a 12-year-old orphan in St. Louis. Another oddity: No death certificate existed for a Clara Morris anywhere close to the 1905 in the timeline of the family story. There was, however, a Clara Morris who died in 1953, but how could that be the one she sought? “I had a long labor,” Klam quips, “but 49 years?”

Finally, a deep dive into the census records revealed the truth. Yes, this was the Clara Morris that Klam was looking for. No, she hadn’t died in 1905 in childbirth. Hers was a different fate: In 1910, her husband had committed her to a Missouri insane asylum, and there, she remained until her death.

Schizophrenia was the diagnosis recorded by the asylum. According to Klam’s cousin Claire, a generation older and more familiar with family stories than Klam, it was postpartum depression that never went away. And how did she know? The family, Claire confessed, had invented the fiction of Clara’s death in childbirth to cover up the truth of her institutionalization. In reality, the sisters had continued to visit their mother until her death.

The shocking revelation propelled Klam onward.

In addition to plodding through old records both in print and online, she embarked on a Morris Sisters travel itinerary. Her stops included the desolate town their family came from in Romania; the unnerving, abandoned asylum in St. Louis where the sisters’ troubled mother had endured for so many decades; the chic addresses of their apartments in New York’s Greenwich Village; and the Southampton, New York, neighborhoods, on Long Island, where they spent their final years. She also employed a devoted research assistant, enlisted the aid of friendly genealogy experts, and pumped a cadre of cousins with long memories for whatever else — fact or fiction — they could tell her.

In the end, she could neither confirm nor debunk two of the more intriguing anecdotes. Left unanswered: Had one of the sisters consulted with President Franklin Roosevelt at the White House about commodity trading in pork bellies? Had another befriended Israeli stateswoman Golda Meir?

But Klam did disprove the claim that the youngest sister, Ruth, was the actual author of the Broadway musical “High Button Shoes.” (Ruth did write a few off-Broadway plays.) And by the end of their lives, the sisters had amassed an estate of close to $10 million, making possible substantial donations to Brandeis University and a library in Southampton.

At times, Klam can ramble and become repetitive, but her lively wit carries us along. With genealogical quests all the rage, Klam’s book serves as a droll guide for other ancestry seekers. It’s also a cautionary tale about the obsessional nature of such a search and the bracing truths that may lie buried beneath the family lore.

The journey into the past led Klam to truths that she could carry forward into her future.

“The person who thought it was her birthright to be incapable of self-sufficiency, the woman who expected the world to be predictable, reliable — she was gone,” Klam writes. Instead, “I was connected to a group of strong women who did what they did and succeeded without the support of men.”

Their grit was always part of her DNA; she just needed to locate it within her.

Diane Cole is book columnist for the Psychotherapy Networker and the author of the memoir “After Great Pain: A New Life Emerges.”