Anthony Marshall sits in a wheelchair as he is pushed into a New York courtroom in June 2013 by his wife, former Mount Desert Island resident Charlene Marshall. Marshall died Sunday in New York City at the age of 90. (Reuters photo)

Brooke Astor’s son, who was convicted of looting his mother’s fortune after she sank into dementia, has died, according to The Washington Post and the New York Times.

Anthony Marshall, who like his famous mother was a seasonal resident of Northeast Harbor on Mount Desert Island, passed away Sunday in New York City, media reports indicate. He was 90 years old.

Astor, who summered for decades at Cove End, overlooking the Northeast Harbor Yacht Club, died in 2007 at age 105. The year before her death, her grandson Phillip Marshall filed a court petition in Manhattan seeking to have his father removed as Astor’s legal guardian, accusing his father of looting Astor’s $180 million dollar estate for his personal gain.

The allegations riveted New York’s high society and were given sensationalized treatment by the city’s tabloid media.

As a result of the court petition, Anthony Marshall was removed as his mother’s guardian and was forced to return items that he had signed over to himself and his wife, Charlene Marshall, who lived in Northeast Harbor and got divorced from a local Episcopal minister two years before she married Marshall in 1992. Among the items Anthony Marshall had to hand over to his mother’s bank were paintings, artwork, family silver, diamond jewelry, and a 10-carat diamond ring.

As part of the 2006 settlement, Charlene Marshall was ordered to sign ownership of Cove End back to her husband, who had transferred the property to himself and then to his wife in 2003.

Prosecution of Anthony Marshall on charges of stealing from his mother were delayed until after his mother died, but Charlene was never charged. Former employees of Astor in Northeast Harbor, and prosecutors at Anthony Marshall’s subsequent criminal trial, suggested that Marshall acted on the behest of his wife.

In 2009, he was convicted of grand larceny, scheming to defraud and other charges, as was his former attorney, Francis X. Morrissey Jr. Both men were allowed to stay out from behind bars while they appealed their convictions. Last year, they exhausted those appeals without overturning their guilty verdicts. Marshall was sent to prison but was paroled two months later due to his own declining health.

Marshall was Astor’s son by her first marriage. She inherited her fortune from her third husband, Vincent Astor, and during her lifetime gave away $200 million of it to charitable and nonprofit causes, including some on MDI.

In her will, Astor gave hundreds of thousands of dollars more to College of the Atlantic, Asticou Azalea Garden, Northeast Harbor Library, Saint Mary’s and Saint Jude’s Parish, and to Maine Community Foundation, which is administering a fund established in Astor’s will for the benefit of local high school students.

Astor’s former real estate in Northeast Harbor has ended up in the control of her daughter-in-law. According to the town of Mount Desert’s online assessing database, Charlene Marshall is the owner or trustee of properties that have a total assessed value of more than $6 million – including Cove End.