A frugal legal secretary from New York City who lived until the age of 96 quietly amassed millions of dollars and donated most of it to charity without telling even her closest friends and relatives.

Sylvia Bloom, who worked at the same law firm as a secretary for 67 years until she retired at 96, amassed more than $9 million simply by observing how the lawyers she served invested their money, the New York Times reported Sunday.

“She was a secretary in an era when they ran their boss’s lives, including their personal investments,” said Jane Lockshin, Bloom’s niece. “So when the boss would buy a stock, she would make the purchase for him, and then buy the same stock for herself, but in a smaller amount because she was on a secretary’s salary.”

But the millions Bloom accumulated among 11 banks and three brokerage houses did not become public knowledge until her $6.24 million donation to the Henry Street Settlement, a social services organization in New York City, was made public last week.

“I realized she had millions and she had never mentioned a word,” said Lockshin, who served as the executor to Bloom’s estate. “I don’t think she thought it was anybody’s business but her own.”

Although a small portion of Bloom’s fortune went to family and friends, she directed most of the money to be donated to charity to help students in need.

“We were all agape, just blown away,” said David Garza, Henry Street’s executive director, who said Bloom’s donation would fund the Expanded Horizons College Success Program.

The program helps underprivileged students prepare for college and graduate from college on time, according to the program’s website.

Lockshin said the other $2 million of Bloom’s bequest would go to Hunter College and another scholarship fund that has yet to be announced.