LOS ANGELES — The estranged brother of Robert Durst, the real estate heir on trial in his best friend's slaying, reluctantly testified Monday that the two never got along and he feared his oldest sibling would kill him.

"He’d like to murder me," Douglas Durst bluntly told jurors in Los Angeles County Superior Court.

Douglas Durst, chairman of one of New York’s largest commercial real estate firms, said he had not seen his brother in 20 years and they had not spoken since 1999. He said Robert Durst was angry and bitter over an acrimonious inheritance settlement for tens of millions of dollars.

Douglas Durst, chairman of the Durst Organization that owns some of Manhattan's premier skyscrapers and 2,500 apartments, said he and his brother had fought since they were children.

In this still image taken from the Law and Crime Network court video, shows Douglas Durst, testifies at his brother's murder trial in Los Angeles Superior Court in Inglewood, Calif. on Monday, June 28, 2021.  (Law & Crime Network via AP, Pool)

In this still image taken from the Law and Crime Network court video, shows Douglas Durst, testifies at his brother's murder trial in Los Angeles Superior Court in Inglewood, Calif. on Monday, June 28, 2021.  (Law & Crime Network via AP, Pool) (Law & Crime Network via AP, Pool)

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"He treated me miserably," Douglas Durst said. "He would fight with me at every chance. He would embarrass me."

Despite the bad blood, Douglas Durst said he was not happy to testify against his brother, who is on trial on charges of fatally shooting Susan Berman in 2000 at her Los Angeles home. He said he cooperated with prosecutors under threat of subpoena.

"There are other places I’d much rather be," he said.

Prosecutors say Berman provided an alibi for Robert Durst after he killed his first wife, Kathie, in 1982 and that he silenced his friend to keep her from telling police what she knew about the disappearance. Robert Durst has pleaded not guilty.

Kathie Durst had told Douglas Durst she planned to seek a divorce from his brother, he testified.

BEVERLY HILLS, CA MARCH 16, 2015: Robert Durst, wealthy NY real estate heir, has been arrested in connection with the murder of his friend Susan Berman. The crime allegedly was commited by Durst inside this home in Beverly Hills in 2000. (Francine Orr/ Los Angeles Times via Getty Images)

BEVERLY HILLS, CA MARCH 16, 2015: Robert Durst, wealthy NY real estate heir, has been arrested in connection with the murder of his friend Susan Berman. The crime allegedly was commited by Durst inside this home in Beverly Hills in 2000. (Francine Orr/ Los Angeles Times via Getty Images)

Douglas Durst said his brother told him that she had vanished a couple of days after he put her on a train to New York City from their lakeside house in Westchester County. Robert Durst said that was the last time he saw his wife.

"His tone was very neutral," Douglas Durst said. "There was no great anxiety in his tone. It seemed a little strange."

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Kathie Durst has never been found, but she was declared legally dead. Robert Durst has long been considered a suspect in her death but has denied any involvement and has never been charged with a crime related to her disappearance.

Robert Durst seen wrapped in blanket during trial on June 14, 2021

Robert Durst seen wrapped in blanket during trial on June 14, 2021 (POOL)

Douglas Durst, tan and wearing a crisp white shirt with French cuffs and a gray mask because of COVID-19 restrictions, cut a much different figure than his ailing brother.

A pale Robert Durst, 78, with a shaven head that reveals a massive scar from removing fluid his skull, was seated in a wheelchair and dressed in brown jail scrubs.

Durst, who has bladder cancer and several other maladies, stood up and addressed the judge to counter a suggestion by Deputy District Attorney John Lewin that he was seeking sympathy from jurors by displaying his urine bag.

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Durst said his head was shaved because it was the only haircut he could get in jail. He said he wants a doctor to remove a catheter.

"I am not seeking sympathy from the jury," Durst said in a throaty voice.