Maryanne Trump Barry, Donald Trump’s older sister, received a threatening letter Friday in Philadelphia.

The federal appeals court judge received the letter a day after the GOP front-runner’s son received a suspicious piece of mail containing white powder, according to NBC News.

#Ohio Maryanne Trump Barry, Donald Trump’s sister, receives threatenin… https://t.co/VNvJJJyPtq pic.twitter.com/QdZYR4wtxk

— Ohio post (@vagrigoreva5245) March 21, 2016

This is the second Trump family member to receive a threatening letter. Eric Trump, the son of Donald Trump, also received a letter on Thursday demanding that his real estate mogul father drop out of the Republican race for the presidential nomination.

Police were called to Eric’s apartment at Trump Parc East after his wife opened a letter and white powder fell out, WABC reported.

Oh no! A suspicious letter containing "white powder" was sent to Eric Trump. https://t.co/9IupuqN4bC pic.twitter.com/9UO93LghAk

— HollywoodLife (@HollywoodLife) March 18, 2016

The mail sent to Eric Trump was postmarked in Massachusetts, police sources said, but preliminary tests deemed substance found inside the letter non-hazardous.

The FBI and Secret Service are investigating the incident, trying to determine if the letters came from the same source.

MORE TRUMP FAMILY THREATS: Judge Maryanne Trump Barry Receives Threatening Letter https://t.co/o0dQ8dbn9Q pic.twitter.com/bM9Bk42FVL

— TRUMPTRAIN (@OnlyHotyP) March 19, 2016

Trump Barry, a 78-year-old judge with the U.S. Circuit Court of Appeals for the 3rd Circuit, came under scrutiny earlier this year when Trump off-handedly said that he would appoint her to the Supreme Court.

Ted Cruz has called Trump Barry a “radical pro-abortion extremist” for her ruling against banning abortions in New Jersey.

NBC said suspicious and threatening packages are not uncommon for high profile personalities.