(CN) - Donald Trump's sister, Senior U.S. Circuit Judge Maryanne Trump Barry, is the second member of the Republican presidential hopeful's family to receive a threatening letter in the mail, warning him to drop out of the race.
The letter sent to Judge Barry's Philadelphia home is said to be similar to a suspicious package Trump's son Eric received on Thursday at his Manhattan apartment on Central Park South.
That letter reportedly contained a white powder that preliminary tests indicated was not hazardous. It also contained a note that warned Trump, the controversial frontrunner for the Republican presidential nomination, to drop out of the race or risk members of his family being harmed.
About the only detail to be made public about the Eric Trump letter is that it was postmarked in Massachusetts. The New York City Police Department, Secret Service and FBI are continuing to investigate.
Authorities didn't go into detail about the contents of the letter mailed to Judge Barry other than to say she received it Friday, and that while it contained no white powder, it also included threats to Trump's family.
In a statements the FBI's Philadelphia office said, "The FBI is aware of the incident and is working closely with the United States Secret Service and U.S. Marshals Service."
Judge Barry, a member of the Philadelphia-based Third Circuit, is in many respects considered the polar opposite of her younger brother. She eschews the spotlight and rarely speaks in public. After Trump joked in February that he would put her on the Supreme Court, his GOP rival, Sen. Ted Cruz of Texas, at one point called her a "hardcore, pro-abortion liberal judge" based on an opinion she wrote in 2000 for a three-judge panel striking down New Jersey's ban on partial-birth abortions.
In fact, Barry was first appointed to the federal bench by President Ronald Reagan. Among the other judges who joined her in the opinion was Samuel Alito, now considered a member of the U.S. Supreme Court's conservative block.
Barry was still on the U.S. district court when Chief Justice William Rehnquist appointed her chair of the Criminal Law Committee of the Judicial Conference of the United States, a position she held until 1996.
President Bill Clinton nominated her for the Third Circuit on June 17, 1999, and she was unanimously confirmed by the U.S. Senate three months later.
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