Accused sex trafficker and pedophile Jeffrey Epstein was often called a billionaire, but that was hard to verify. At the time of his death, about $550 million of his purported wealth was verifiable. Epstein was found dead in his jail cell at the Metropolitan Correctional Center on the morning of August 10. He was 66. Epstein was not married and didn't have any children. He left behind a younger brother, Mark Epstein. Who is Mark Epstein?

1. His childhood nickname was Puggie

Mark Epstein is two years younger than Jeffrey. They are the only children of Seymour and Pauline Epstein and grew up on Maple Avenue in Sea Gate, Brooklyn. Mark's childhood nickname was Puggie. Epstein's was Bear. Their parents were immigrants and working class.The Daily Beast reported that Mark once ran a T-shirt screen printing business before going into real estate. Reportedly, Mark offered his Florida home as collateral to help his brother make bail when he was arrested in July 2019. Epstein was ultimately denied bail by the judge. 

2. He flew on his brother's jet with Donald Trump

Back in 2015, Mark testified in a deposition that he flew on his brother's private jet along with Donald Trump. Mark testified that his brother and Trump were "friends." When he was asked why Trump was on that flight, Mark said: "You'll have to ask Donald. I think he wanted a ride back to New York."

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3. Various business

Mark Epstein attended the art school Cooper Union and Stony Brook University. In 1984, he ran Atelier Enterprises, Inc.. a charter/leasing company. He set up Epstein Acquisition in 1987 and dissolved it in 2015. Saint Model And Talent as incorporated in 2005. He began investing in New York real estate in the early 1990s.

4. He was accused of financial mismanagement

Mark Epstein was the chairman of the board of Cooper Union. He was vice chairman from 2007 to 2009 and chairman from 2009 until 2013. Art In America magazine reported that during his time as chairman, Mark was accused of financial mismangement. Mark was described as being "intimately involved in most of Cooper Union's worst decisions."

RELATED: Jeffrey Epstein Bought Nadia Marcinko From Her Family To Be His Sex Slave — Where Is She Today?

5. Jeffrey rented apartments in one of Mark's buildings

Mark's LinkedIn page indicates  he's owned Ossa Properties since 1992. The Daily Caller reported that Mark bought an apartment building in which a number of Jeffrey Epstein's known associates have lived or worked  — including Maritza Vasquez, the bookkeeper for a modeling agency Jeffrey invested $1 million in. Jeffrey's attorney used one of Mark's apartments as his primary business office. Mark bought the building on East 66th Street in New York City on his brother's advice from billionaire Limited clothing brand founder Les Wexner.

In Jeffrey's address book, there were 25 blacked out phone numbers for people in apartments in his brother's building, which was listed as "Apt. for models." The entity that owned Jeffrey's East 71st Street mansion listed an apartment in the East 66th Street building as it's mailing address. Lesley Groff, who's accused of helping book Epstein’s sexual “massages” (read: sex) with underage girls, reportedly worked out of the 66th Street building, according to a 2009 deposition of Epstein’s personal pilot. Two of Epstein's assistants, Sarah Kellen and Nadia Marcinko, registered businesses out of the same 66th street building under fake names after Epstein’s arrest, according to the Guardian.

Mark Epstein told the Wall Street Journal via email: “Other than the obvious relationship of being brothers, the only other relationship between Jeffrey and I is as landlord/tenant."

6. More Les Wexner connections

Jeffrey and Mark Epstein also had a 200 unit condo building on the Upper East Side of Manhattan that was once owned by Les Wexner. J. Epstein & Co. bought the building in the early 1990s. Mark Epstein was, at one time, the president of that company. 

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Amy Lamare is a Los Angeles based freelance writer covering entertainment, pop culture, beauty, fashion, fitness, technology, and the intersection of technology, business, and philanthropy. You can find her on Instagram and Facebook.