President Donald Trump's younger brother, Robert, is hospitalized in New York

President Donald Trump's younger brother, Robert Trump, has been hospitalized in New York, according to the White House.

The president is expected to visit his 72-year-old brother at a hospital in Manhattan on Friday, according to White House spokesman Judd Deere. Trump was already scheduled to visit his property in Bedminster, New Jersey, on Friday.

The White House did not immediately release details about why Robert Trump had been hospitalized, but officials said that he was seriously ill.

“I have a wonderful brother. We’ve had a great relationship for a long time, from day one," Trump told reporters before departing for New York. “He’s in the hospital right now, and hopefully he’ll be all right. But he’s having a hard time."

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Robert Trump, one of four siblings to the president, recently filed a lawsuit on behalf of the Trump family seeking to stop publication of a tell-all book by the president’s niece Mary titled “Too Much and Never Enough."

The president has said that Mary Trump’s book was a violation of a nondisclosure agreement she signed in connection to a financial settlement she received from the Trump family. Mary is the daughter of the brothers' eldest sibling, Fred Trump Jr., who struggled with alcoholism and died in 1981 at the age of 43.

No family members joined Fred Jr., who was known as Freddy, at the hospital on the night he died, Mary Trump said, adding that Donald Trump went to the movies with another sibling instead.

Robert Trump had previously worked for his older brother as a top executive at the Trump Organization. Once a regular bold face name in Manhattan's social pages, he has kept a lower profile in recent years. He married his longtime girlfriend, Ann Marie Pallan, in March, according to the New York Post. He divorced his first wife, Blaine Trump, more than a decade ago.

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In a 2016 interview with the New York Post, he described himself as a big supporter of his brother's run for the White House.

“I support Donald one thousand percent,” Robert Trump said.

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