This is the first report on a two-part story revealing new research reported on Vivian Maier. The second report is now published,

Who was Vivian Maier?

Ann Marks, who spent months researching the upbringing of the Chicago nanny who is now heralded as a master of street photography, still doesn’t have an answer. But Ms. Marks — who has no background in photography and started researching Maier only after seeing a documentary about her life — has learned a great deal about Maier’s family history.

Maier’s parents were unhappy in their marriage from the day she was born. She grew up in the shadow of an older brother who spent time in a vocational school and, later in life, a psychiatric hospital. Both Maier children spent time living with guardians other than their parents, from grandparents to foster parents. Meanwhile, both of Maier’s grandmothers had negative things to say about their own children, her parents.

And yet some of the family difficulties she encountered in childhood may have contributed to the photographer she became. From early childhood, Maier spent a significant amount of time with a woman named Jeanne Bertrand, who worked as a professional photographer, as well as other positive female role models.

“There’s always this incredible elusiveness about the maker of those photos,” said Jeffrey Goldstein, who was one of the first to acquire and champion her work. “To me, it’s miraculous,” he said of Ms. Marks’s research. “It’s absolutely miraculous.”

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He says Ms. Marks’s research is “equivalent to, if not more important than, all of the work that John and I have done,” referring to John Maloof, who bought some of Maier’s negatives at a Chicago auction in 2007. Mr. Maloof printed more than 80 Vivian Maier images for her first exhibit in Chicago in 2011 and later was co-director of “Finding Vivian Maier,” an Oscar-nominated documentary about her.

“She’s basically picked up the obsession that I had in making the film,” Mr. Maloof said. “But she’s picked it up where I left off and continued with it. And she filled in a lot of blanks.”

The film spurred Ms. Marks, a retired business executive who lives in New York, into action when she first saw it just over a year ago. She didn’t know what she was getting into. Afterward, she said she felt that “there were so many loose ends, and mysteries,” and decided to do a little sleuthing.

“I wanted to challenge myself and show myself that I could find someone,” Ms. Marks said. “Because I felt in the Internet age, when there’s so much information, people can’t disappear anymore. And then, of course, once I got started, I couldn’t stop.”

Vivian Maier was obsessed. She was obsessed with the practice of taking photographs — which she did for most of her life, until she died in Chicago in 2009 — and she was obsessed with details of daily life on the streets, from newspapers to men wearing hats.

The same can be said for Mr. Maloof and Mr. Goldstein, who sold his collection of negatives to the Stephen Bulger Gallery in Toronto. Both men became obsessed with telling Maier’s story. (One result of the publicity their efforts received is a legal battle about the heir to Maier’s assets.)

Ms. Marks’s obsession is with the gaps in Maier’s story. As she kept researching, though, she got stuck. She reached out to Mr. Maloof and Mr. Goldstein, assuming they knew things she didn’t. When it became clear that neither had the answers she wanted, she said, “That’s when I really started researching.”

Ms. Marks ventured beyond her computer and into archives in New York City, where Maier was born in 1926. She pored over microfilm at the New York Public Library looking for birth records and at the Surrogate Court in Queens and Manhattan, in search of wills. In September, The Chicago Tribune spotlighted one of her discoveries: insights into the life of Maier’s brother, Karl, who died in 1977 at a New Jersey rest home.

“Because I felt in the Internet age, when there’s so much information, people can’t disappear anymore.” — Ann Marks

She also began looking at the photos, including prints Maier made herself that had handwritten captions. In the fall, Ms. Marks found dozens of photographs taken at an estate in Brookville, on Long Island, including photos of a toddler. The name “John Akin” was written on one of the prints. When she looked the name up online, she eventually came across John’s daughter, a photographer named Gwen.

“Of course I was familiar with her work,” Ms. Akin said of Maier, “but I had no clue whatsoever that there could possibly be a connection there.” She was shocked to see herself in the photos, but unable to help Ms. Marks fill in many blanks.

“I did remember that I had a babysitter back then,” said Ms. Akin, 65. But she was only a toddler in the photos, and so she recalls little with clarity. One thing she did notice upon seeing the photos, she said, was that Maier — who was then in her 20s — had yet to find herself as a photographer.

Ms. Akin could see the “realization and recognition of light and shadow and all that stuff,” she said. “It was later on that she hit her stride.”

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That year, 1952, Maier invested in a medium-format twin-lens Rolleiflex.

The breakthrough that has most excited Ms. Marks was the moment she found the baptismal record for Maier’s brother, Karl, who was also called Charles or Carl. One night while watching television, she scrolled through pages and pages of documents online and located the death record for Maier’s only sibling, whose life included run-ins with the law, drug addiction, a dishonorable discharge from the Army and, ultimately, a diagnosis of schizophrenia.

And there was more. According to documents and letters Ms. Marks found, Maier was not raised in a happy household. Her world included unhappy marriages, disagreements and alcoholism. Her own mother didn’t include Maier’s name in her will.

Ms. Marks’s findings are significant, not only in filling in so many blanks about how Vivian Maier came to be an extraordinary, secretive photographer, but also in helping to explain her worldview.

“It suddenly makes sense to me why she selected the imagery that she did,” Mr. Goldstein said of the insights into Maier’s upbringing. “I think the edginess, which is one of the things I love — there’s this underlying edginess that runs through her work. And she had a very edgy life.”

While records excite Ms. Marks, what she wants most is to find more people who knew the Maier family. She isn’t finished looking. She is also not the only person studying the circumstances of Maier’s life, of which many details are still very murky.

Among the questions she hopes to answer: What kind of relationship did Maier have with her brother?

“Vivian was a compassionate person and cared about the underdog,” Ms.Marks mused, “so why didn’t she have a relationship with the brother?”

Thesecond part of this story is now published. To see all of Ann Marks’s research on the family history of Vivian Maier, visit her website.Ms. Marks worked closely with Francoise Perron, who lives in France. Work by Maier is showing at the Merry Karnowsky Gallery in Los Angeles.

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